2021: d12: ex2: add solution

2021: d12: ex2: add input
2021: d12: ex1: add solution
2021-12-12 15:13:41 +01:00 · 2021-12-12 15:13:21 +01:00 · 2021-12-12 15:13:10 +01:00 · 2021-12-12 15:12:36 +01:00 · 2021-12-11 14:12:19 +01:00 · 2021-12-11 14:12:08 +01:00
45 changed files with 8251 additions and 0 deletions
--- a/2021/d01/ex2/ex2.py
+++ b/2021/d01/ex2/ex2.py
@ -0,0 +1,30 @@
+#!/usr/bin/env python
+
+import collections
+import itertools
+import sys
+from typing import List
+
+
+def sliding_window(iterable, n):
+    it = iter(iterable)
+    window = collections.deque(itertools.islice(it, n), maxlen=n)
+    if len(window) == n:
+        yield tuple(window)
+    for x in it:
+        window.append(x)
+        yield tuple(window)
+
+
+def solve(input: List[int]) -> int:
+    windowed = [sum(window) for window in sliding_window(input, 3)]
+    return sum(prev < cur for (prev, cur) in itertools.pairwise(windowed))
+
+
+def main() -> None:
+    input = [int(line) for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d02/ex1/ex1.py
+++ b/2021/d02/ex1/ex1.py
@ -0,0 +1,32 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from typing import List
+
+
+def solve(input: List[str]) -> int:
+    x, y = 0, 0
+
+    for instruction in input:
+        dir, length = instruction.split(" ")
+        length = int(length)
+        if dir == "forward":
+            x += length
+        elif dir == "down":
+            y += length
+        elif dir == "up":
+            y -= length
+        else:
+            assert False
+
+    return x * y
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d02/ex1/input
+++ b/2021/d02/ex1/input
--- a/2021/d02/ex2/ex2.py
+++ b/2021/d02/ex2/ex2.py
@ -0,0 +1,33 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from typing import List
+
+
+def solve(input: List[str]) -> int:
+    x, y, aim = 0, 0, 0
+
+    for instruction in input:
+        dir, length = instruction.split(" ")
+        length = int(length)
+        if dir == "forward":
+            x += length
+            y += length * aim
+        elif dir == "down":
+            aim += length
+        elif dir == "up":
+            aim -= length
+        else:
+            assert False
+
+    return x * y
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d02/ex2/input
+++ b/2021/d02/ex2/input
--- a/2021/d03/ex1/ex1.py
+++ b/2021/d03/ex1/ex1.py
@ -0,0 +1,30 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from typing import List
+
+
+def solve(input: List[int]) -> int:
+    gamma, epsilon = 0, 0
+    bit = 1
+
+    while any(map(bool, input)):
+        num_bits = sum(n % 2 for n in input)
+        if num_bits >= len(input) / 2:
+            gamma += bit
+        else:
+            epsilon += bit
+        input = [n // 2 for n in input]
+        bit *= 2
+
+    return gamma * epsilon
+
+
+def main() -> None:
+    input = [int(line, 2) for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d03/ex1/input
+++ b/2021/d03/ex1/input
--- a/2021/d03/ex2/ex2.py
+++ b/2021/d03/ex2/ex2.py
@ -0,0 +1,68 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from copy import deepcopy
+from typing import List
+
+
+def solve(input: List[int]) -> int:
+    def highest_pow2(n: int) -> int:
+        return len(bin(n)) - 2 - 1  # '0b' prefix, and off-by-one
+
+    def count_bits_at(input: List[int], bit: int) -> int:
+        return sum((n & pow(2, bit)) != 0 for n in input)
+
+    def filter_by_bit_value(input: List[int], bit: int, value: int) -> List[int]:
+        # Simplify the filter by mapping the value to the actual power of 2
+        if value != 0:
+            value = pow(2, bit)
+        return list(filter(lambda n: (n & pow(2, bit)) == value, input))
+
+    def filter_oxygen(input: List[int], bit: int) -> List[int]:
+        # No further processing needed
+        if len(input) <= 1:
+            return input
+
+        num_bits = count_bits_at(input, bit)
+        # Keep 1s on equality
+        if num_bits >= len(input) / 2:
+            return filter_by_bit_value(input, bit, 1)
+        else:
+            return filter_by_bit_value(input, bit, 0)
+
+    def filter_co2(input: List[int], bit: int) -> List[int]:
+        # No further processing needed
+        if len(input) <= 1:
+            return input
+
+        num_bits = count_bits_at(input, bit)
+        # Keep 0s on equality
+        if num_bits < len(input) / 2:
+            return filter_by_bit_value(input, bit, 1)
+        else:
+            return filter_by_bit_value(input, bit, 0)
+
+    oxygen, co2 = 0, 0
+    max_bit = max(highest_pow2(n) for n in input)
+    oxygen_input, co2_input = deepcopy(input), deepcopy(input)
+
+    for bit in range(max_bit, -1, -1):
+        oxygen_input = filter_oxygen(oxygen_input, bit)
+        co2_input = filter_co2(co2_input, bit)
+
+        if len(oxygen_input) == 1:
+            oxygen = oxygen_input[0]
+        if len(co2_input) == 1:
+            co2 = co2_input[0]
+
+    return oxygen * co2
+
+
+def main() -> None:
+    input = [int(line, 2) for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d03/ex2/input
+++ b/2021/d03/ex2/input
--- a/2021/d04/ex1/ex1.py
+++ b/2021/d04/ex1/ex1.py
@ -0,0 +1,59 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from typing import List, Tuple
+
+Board = List[List[int]]
+
+
+def solve(input: List[str]) -> int:
+    def parse_input() -> Tuple[List[int], List[Board]]:
+        def listify(line: str, delim: str = " ") -> List[int]:
+            return [int(n) for n in line.split(delim) if n != ""]
+
+        draw_order = listify(input[0], delim=",")
+        boards: List[Board] = []
+        for l in input[1:]:
+            if l == "":
+                boards.append([])
+                continue
+            boards[-1].append(listify(l))
+
+        return draw_order, boards
+
+    def bingo(board: Board, draw: List[int]) -> bool:
+        assert len(board) == len(board[0])
+
+        def line(l: int) -> bool:
+            return all(n in draw for n in board[l])
+
+        def row(r: int) -> bool:
+            return all(board[i][r] in draw for i in range(len(board)))
+
+        lines = [line(i) for i in range(len(board))]
+        rows = [row(i) for i in range(len(board[0]))]
+
+        return any(itertools.chain(lines, rows))
+
+    draw_order, boards = parse_input()
+
+    draw = []
+    for d in draw_order:
+        draw.append(d)
+        for b in boards:
+            if not bingo(b, draw):
+                continue
+            return d * sum(n for n in itertools.chain.from_iterable(b) if n not in draw)
+
+    # Sanity check
+    assert False
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d04/ex1/input
+++ b/2021/d04/ex1/input
@ -0,0 +1,601 @@
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--- a/2021/d04/ex2/ex2.py
+++ b/2021/d04/ex2/ex2.py
@ -0,0 +1,69 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from typing import List, Tuple
+
+Board = List[List[int]]
+
+
+def solve(input: List[str]) -> int:
+    def parse_input() -> Tuple[List[int], List[Board]]:
+        def listify(line: str, delim: str = " ") -> List[int]:
+            return [int(n) for n in line.split(delim) if n != ""]
+
+        draw_order = listify(input[0], delim=",")
+        boards: List[Board] = []
+        for l in input[1:]:
+            if l == "":
+                boards.append([])
+                continue
+            boards[-1].append(listify(l))
+
+        return draw_order, boards
+
+    def bingo(board: Board, draw: List[int]) -> bool:
+        assert len(board) == len(board[0])
+
+        def line(l: int) -> bool:
+            return all(n in draw for n in board[l])
+
+        def row(r: int) -> bool:
+            return all(board[i][r] in draw for i in range(len(board)))
+
+        lines = [line(i) for i in range(len(board))]
+        rows = [row(i) for i in range(len(board[0]))]
+
+        return any(itertools.chain(lines, rows))
+
+    draw_order, boards = parse_input()
+
+    draw = []
+    losers = set(range(len(boards)))
+
+    for d in draw_order:
+        draw.append(d)
+        for i, b in enumerate(boards):
+            # Stop early if we already know this board wins
+            if i not in losers:
+                continue
+            if not bingo(b, draw):
+                continue
+            # Discard winners until the last one
+            if len(losers) != 1:
+                losers.discard(i)
+                continue
+            # At thid point, we must be looking at the last winning board
+            return d * sum(n for n in itertools.chain.from_iterable(b) if n not in draw)
+
+    # Sanity check
+    assert False
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d04/ex2/input
+++ b/2021/d04/ex2/input
@ -0,0 +1,601 @@
+85,84,30,15,46,71,64,45,13,90,63,89,62,25,87,68,73,47,65,78,2,27,67,95,88,99,96,17,42,31,91,98,57,28,38,93,43,0,55,49,22,24,82,54,59,52,3,26,9,32,4,48,39,50,80,21,5,1,23,10,58,34,12,35,74,8,6,79,40,76,86,69,81,61,14,92,97,19,7,51,33,11,77,75,20,70,29,36,60,18,56,37,72,41,94,44,83,66,16,53
+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
+52 69 77 41  8
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+
+93  2 70 26  4
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+
+76 78 70 24 75
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+
+34 39 94 84  0
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+
+50 66 43 39 16
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+
+70 56 80 12 11
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+20 23 26 29 14
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+
+78 23 13 37 94
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+
+64 37 93 48 34
+22 81 58  5 13
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+83 75 96 91 88
+
+1 54 88 45 90
+81 78 19  8 40
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+
+2 62 96 60 81
+51  1 34 48 25
+78 13 74 65 42
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+85 88 53 68 76
+
+57 95 40 92 27
+65 37 42 90  9
+17 72 78 43 45
+87 28 48 81 79
+7  4 24 67 70
--- a/2021/d05/ex1/ex1.py
+++ b/2021/d05/ex1/ex1.py
@ -0,0 +1,65 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from collections import Counter
+from dataclasses import dataclass
+from typing import Iterable, List, Tuple
+
+
+@dataclass
+class Point:
+    x: int
+    y: int
+
+
+Line = Tuple[Point, Point]
+
+
+def solve(input: List[str]) -> int:
+    def parse_line(line: str) -> Line:
+        def parse_point(point: str) -> Point:
+            x, y = map(int, point.split(","))
+            return Point(x, y)
+
+        p1, p2 = map(parse_point, line.split(" -> "))
+        return (p1, p2)
+
+    def is_of_interest(line: Line) -> bool:
+        p1, p2 = line
+        return p1.x == p2.x or p1.y == p2.y
+
+    def line_to_points(line: Line) -> Iterable[Point]:
+        def inclusive_range_any_order(a: int, b: int) -> Iterable[int]:
+            if a < b:
+                yield from range(a, b + 1)
+            else:
+                yield from range(a, b - 1, -1)
+
+        p1, p2 = line
+
+        if p1.x == p2.x:
+            for y in inclusive_range_any_order(p1.y, p2.y):
+                yield (p1.x, y)
+            return
+
+        if p1.y == p2.y:
+            for x in inclusive_range_any_order(p1.x, p2.x):
+                yield (x, p1.y)
+            return
+
+        assert False  # Sanity check
+
+    lines = list(filter(is_of_interest, map(parse_line, input)))
+    counts = Counter(itertools.chain.from_iterable(line_to_points(l) for l in lines))
+
+    return sum(counts[p] > 1 for p in counts)
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d05/ex1/input
+++ b/2021/d05/ex1/input
@ -0,0 +1,500 @@
+284,294 -> 733,743
+625,347 -> 653,375
+561,848 -> 561,181
+836,102 -> 836,339
+946,941 -> 22,17
+18,954 -> 956,16
+370,142 -> 370,700
+990,966 -> 677,966
+366,603 -> 366,465
+728,942 -> 57,271
+615,493 -> 847,493
+584,281 -> 301,281
+125,356 -> 301,180
+941,569 -> 555,183
+151,116 -> 509,116
+41,18 -> 841,818
+627,670 -> 627,630
+965,472 -> 965,100
+93,404 -> 330,641
+475,963 -> 475,514
+389,389 -> 389,326
+842,565 -> 842,576
+454,700 -> 650,700
+73,810 -> 73,319
+450,212 -> 450,284
+316,392 -> 316,697
+915,592 -> 578,592
+622,485 -> 434,485
+109,853 -> 952,10
+305,73 -> 305,222
+27,489 -> 157,489
+191,979 -> 867,979
+527,329 -> 527,292
+301,645 -> 301,162
+639,730 -> 176,730
+46,964 -> 46,458
+727,422 -> 435,714
+28,552 -> 404,552
+33,108 -> 33,21
+227,249 -> 327,249
+414,903 -> 784,903
+69,422 -> 888,422
+422,924 -> 103,605
+793,353 -> 450,10
+714,682 -> 714,972
+201,745 -> 410,745
+408,713 -> 408,847
+174,842 -> 818,198
+863,353 -> 775,353
+199,780 -> 670,780
+877,947 -> 340,410
+163,202 -> 163,91
+955,919 -> 955,585
+836,271 -> 533,271
+258,366 -> 728,836
+582,749 -> 582,12
+80,40 -> 80,704
+287,213 -> 287,635
+390,546 -> 390,194
+837,511 -> 538,810
+473,281 -> 902,281
+851,865 -> 731,745
+918,59 -> 445,532
+796,215 -> 796,248
+875,111 -> 604,111
+660,805 -> 538,805
+507,850 -> 145,850
+585,861 -> 585,52
+426,74 -> 700,348
+206,405 -> 529,405
+418,333 -> 418,17
+368,457 -> 33,792
+186,81 -> 957,852
+505,283 -> 113,283
+20,878 -> 462,878
+750,237 -> 69,918
+15,280 -> 358,623
+798,981 -> 500,683
+965,970 -> 22,970
+950,970 -> 148,970
+660,392 -> 660,884
+862,405 -> 862,527
+801,283 -> 801,361
+71,837 -> 136,837
+651,438 -> 945,144
+524,607 -> 614,517
+348,955 -> 138,955
+957,164 -> 404,717
+531,581 -> 454,504
+710,185 -> 710,271
+822,86 -> 822,966
+745,233 -> 490,488
+350,823 -> 663,823
+824,67 -> 447,444
+846,667 -> 796,617
+666,24 -> 666,906
+640,39 -> 640,145
+654,481 -> 985,481
+581,894 -> 416,729
+443,11 -> 697,11
+318,627 -> 799,146
+113,78 -> 891,856
+181,149 -> 179,151
+451,74 -> 451,262
+458,726 -> 314,726
+218,662 -> 533,662
+965,108 -> 527,108
+782,481 -> 896,367
+557,927 -> 557,938
+506,242 -> 941,677
+948,778 -> 948,629
+567,816 -> 567,956
+323,773 -> 323,364
+864,980 -> 864,12
+611,699 -> 611,886
+613,392 -> 901,104
+528,905 -> 156,905
+632,206 -> 798,40
+338,237 -> 919,818
+256,889 -> 11,644
+835,52 -> 55,832
+464,144 -> 322,144
+254,747 -> 254,509
+866,892 -> 866,916
+827,946 -> 30,149
+899,84 -> 177,806
+134,634 -> 357,634
+781,492 -> 244,492
+817,762 -> 817,976
+818,749 -> 818,860
+262,480 -> 263,480
+409,576 -> 409,698
+242,151 -> 981,890
+149,519 -> 149,557
+42,990 -> 42,930
+687,974 -> 50,337
+758,382 -> 465,382
+760,861 -> 760,934
+17,835 -> 17,915
+645,923 -> 645,648
+702,116 -> 72,746
+153,162 -> 955,964
+185,101 -> 918,834
+554,179 -> 554,353
+879,673 -> 879,949
+368,13 -> 368,512
+582,105 -> 591,114
+146,291 -> 600,745
+609,538 -> 930,538
+320,604 -> 320,146
+566,698 -> 443,575
+167,708 -> 844,31
+712,630 -> 712,421
+912,930 -> 64,82
+980,931 -> 87,38
+23,893 -> 888,28
+640,435 -> 676,435
+701,516 -> 190,516
+684,145 -> 62,767
+127,471 -> 91,435
+685,197 -> 78,197
+103,493 -> 103,522
+309,986 -> 309,850
+938,270 -> 938,300
+295,72 -> 354,72
+948,889 -> 948,455
+254,733 -> 254,175
+95,329 -> 942,329
+19,672 -> 19,445
+206,807 -> 206,934
+886,961 -> 886,690
+117,386 -> 117,292
+199,59 -> 668,528
+299,263 -> 299,878
+28,295 -> 638,905
+10,140 -> 276,406
+279,526 -> 921,526
+485,128 -> 856,499
+418,398 -> 186,398
+296,577 -> 296,521
+514,261 -> 10,765
+691,673 -> 776,758
+131,430 -> 152,430
+858,85 -> 62,85
+394,846 -> 270,970
+827,913 -> 827,376
+634,669 -> 910,669
+12,53 -> 945,986
+782,467 -> 782,421
+159,832 -> 109,832
+793,807 -> 79,93
+120,584 -> 356,584
+645,16 -> 645,355
+526,685 -> 217,376
+296,305 -> 296,929
+954,144 -> 954,839
+748,88 -> 103,733
+523,804 -> 473,754
+524,316 -> 524,756
+696,183 -> 912,183
+288,564 -> 55,797
+568,103 -> 568,348
+468,626 -> 682,412
+163,163 -> 961,961
+762,824 -> 27,89
+623,625 -> 32,34
+865,343 -> 490,718
+259,458 -> 259,33
+944,660 -> 944,176
+781,804 -> 826,759
+15,702 -> 15,553
+403,310 -> 918,825
+438,734 -> 835,734
+825,13 -> 825,245
+129,611 -> 370,611
+49,939 -> 172,939
+687,906 -> 687,532
+629,482 -> 273,126
+727,218 -> 424,218
+447,451 -> 233,451
+142,779 -> 813,779
+527,27 -> 527,804
+482,55 -> 482,200
+39,264 -> 806,264
+884,636 -> 458,636
+467,121 -> 199,389
+856,925 -> 856,666
+666,359 -> 378,359
+11,946 -> 705,946
+491,281 -> 940,730
+86,112 -> 918,944
+974,807 -> 974,707
+445,67 -> 914,536
+953,394 -> 953,822
+468,398 -> 157,87
+231,620 -> 231,646
+979,869 -> 979,911
+450,330 -> 450,79
+675,659 -> 617,659
+66,181 -> 66,723
+181,406 -> 181,192
+908,334 -> 908,526
+254,891 -> 282,891
+777,791 -> 127,141
+469,58 -> 694,58
+954,957 -> 566,569
+957,957 -> 123,123
+741,359 -> 741,986
+763,526 -> 763,101
+857,427 -> 600,170
+527,756 -> 490,719
+625,249 -> 397,249
+798,702 -> 712,702
+868,75 -> 868,853
+332,296 -> 332,629
+211,829 -> 100,940
+12,139 -> 12,218
+655,978 -> 655,242
+99,852 -> 855,96
+486,267 -> 486,855
+474,90 -> 474,244
+948,491 -> 186,491
+896,59 -> 278,677
+295,732 -> 629,732
+860,936 -> 860,556
+143,790 -> 143,26
+371,847 -> 395,847
+739,301 -> 739,44
+384,716 -> 748,716
+848,423 -> 848,923
+855,23 -> 218,660
+381,805 -> 381,438
+451,610 -> 91,610
+906,957 -> 191,957
+118,675 -> 169,675
+836,818 -> 95,818
+368,945 -> 825,488
+165,299 -> 899,299
+392,327 -> 926,861
+663,16 -> 131,548
+630,302 -> 888,302
+206,869 -> 206,331
+979,413 -> 979,204
+894,860 -> 62,28
+444,897 -> 962,379
+550,158 -> 550,885
+845,736 -> 811,736
+846,857 -> 12,857
+981,730 -> 981,154
+694,835 -> 88,835
+21,101 -> 21,385
+19,960 -> 964,15
+283,721 -> 450,721
+59,136 -> 758,835
+287,313 -> 719,313
+471,252 -> 849,630
+682,189 -> 168,189
+10,921 -> 774,157
+884,598 -> 884,540
+207,615 -> 207,443
+627,408 -> 67,408
+285,36 -> 285,792
+116,585 -> 254,585
+183,86 -> 183,702
+220,138 -> 868,138
+833,68 -> 286,615
+367,534 -> 766,534
+907,514 -> 621,228
+133,593 -> 133,581
+164,727 -> 768,123
+566,227 -> 566,555
+983,988 -> 105,110
+620,177 -> 620,821
+612,413 -> 612,176
+168,889 -> 168,210
+871,487 -> 559,175
+399,870 -> 761,870
+236,976 -> 582,630
+699,216 -> 699,887
+153,745 -> 790,745
+444,749 -> 444,257
+808,165 -> 939,165
+546,525 -> 95,976
+583,179 -> 373,389
+235,816 -> 840,816
+744,89 -> 832,89
+425,317 -> 465,357
+267,235 -> 114,82
+887,59 -> 572,374
+808,237 -> 808,626
+431,352 -> 400,383
+815,376 -> 815,905
+249,218 -> 989,958
+120,435 -> 357,198
+807,551 -> 490,234
+910,524 -> 910,725
+802,304 -> 447,659
+789,228 -> 678,339
+229,322 -> 52,322
+658,393 -> 506,393
+378,438 -> 378,569
+163,981 -> 473,671
+537,984 -> 935,586
+58,945 -> 966,37
+132,696 -> 565,263
+136,813 -> 136,284
+606,656 -> 298,348
+533,572 -> 673,712
+872,912 -> 301,341
+16,287 -> 16,613
+571,541 -> 980,950
+117,495 -> 35,495
+85,79 -> 682,676
+425,431 -> 117,739
+982,984 -> 10,12
+28,75 -> 431,478
+259,529 -> 259,436
+762,267 -> 170,859
+323,135 -> 929,741
+81,238 -> 561,718
+128,213 -> 876,961
+649,466 -> 649,540
+715,863 -> 119,863
+830,624 -> 794,660
+123,968 -> 977,114
+489,466 -> 489,811
+27,10 -> 980,963
+255,732 -> 255,484
+574,829 -> 431,829
+548,743 -> 22,217
+903,297 -> 903,763
+684,774 -> 64,154
+260,823 -> 683,823
+422,211 -> 422,826
+10,196 -> 988,196
+108,802 -> 15,802
+104,70 -> 104,452
+885,59 -> 885,36
+68,854 -> 68,774
+731,935 -> 731,718
+657,986 -> 617,986
+732,292 -> 732,32
+841,56 -> 841,83
+74,108 -> 862,896
+654,895 -> 323,895
+374,952 -> 374,217
+90,723 -> 750,63
+246,89 -> 911,754
+453,301 -> 755,301
+983,988 -> 23,28
+81,705 -> 133,757
+752,743 -> 752,397
+53,243 -> 449,639
+451,811 -> 451,187
+26,672 -> 26,699
+254,861 -> 943,861
+643,740 -> 643,966
+486,655 -> 149,318
+375,146 -> 375,973
+76,293 -> 103,293
+246,398 -> 246,248
+324,392 -> 595,121
+130,577 -> 131,577
+380,623 -> 549,454
+224,181 -> 985,942
+310,223 -> 310,594
+23,982 -> 23,738
+19,858 -> 832,858
+726,531 -> 726,578
+730,433 -> 196,433
+606,599 -> 242,599
+444,832 -> 444,238
+198,870 -> 47,870
+944,473 -> 795,473
+737,386 -> 178,945
+328,902 -> 328,644
+422,851 -> 567,851
+674,781 -> 215,781
+920,757 -> 302,757
+225,932 -> 640,517
+359,337 -> 791,337
+935,430 -> 935,262
+772,850 -> 280,358
+175,829 -> 175,451
+938,204 -> 234,908
+253,749 -> 308,749
+704,458 -> 468,458
+222,95 -> 743,616
+968,840 -> 123,840
+491,619 -> 491,889
+979,580 -> 979,459
+901,193 -> 171,923
+246,155 -> 246,680
+711,755 -> 247,755
+671,734 -> 475,734
+803,783 -> 129,109
+145,890 -> 920,115
+463,521 -> 463,700
+782,99 -> 782,311
+547,467 -> 630,467
+14,88 -> 795,869
+653,899 -> 653,90
+488,874 -> 488,570
+93,879 -> 645,327
+320,658 -> 40,938
+611,246 -> 611,22
+258,935 -> 258,829
+931,436 -> 931,263
+252,460 -> 252,461
+490,382 -> 965,382
+242,89 -> 242,617
+271,111 -> 595,435
+462,706 -> 242,486
+557,328 -> 747,328
+486,99 -> 486,333
+156,40 -> 488,372
+323,482 -> 138,297
+595,539 -> 812,756
+923,861 -> 377,315
+934,952 -> 256,274
+314,777 -> 314,12
+508,47 -> 508,144
+888,807 -> 701,807
+745,774 -> 878,907
+740,716 -> 740,215
+62,43 -> 62,12
+571,196 -> 454,196
+568,107 -> 408,107
+549,676 -> 404,676
+595,573 -> 595,970
+148,168 -> 193,123
+763,71 -> 759,71
+797,64 -> 307,64
+959,984 -> 32,57
+457,562 -> 634,562
+127,521 -> 601,47
+112,296 -> 112,120
+148,755 -> 451,755
+636,494 -> 870,494
+910,242 -> 945,277
+912,911 -> 912,892
+759,815 -> 759,314
+391,285 -> 391,959
+455,460 -> 182,460
+112,78 -> 112,385
+842,179 -> 842,592
+236,424 -> 421,424
+508,907 -> 30,907
+637,219 -> 34,822
+503,375 -> 503,205
+570,533 -> 626,533
+658,11 -> 658,94
+179,286 -> 326,433
+918,214 -> 200,932
+339,887 -> 81,887
+794,91 -> 50,835
+225,356 -> 225,261
+80,160 -> 80,335
+148,64 -> 847,763
+595,393 -> 941,393
--- a/2021/d05/ex2/ex2.py
+++ b/2021/d05/ex2/ex2.py
@ -0,0 +1,60 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from collections import Counter
+from dataclasses import dataclass
+from typing import Iterable, List, Tuple
+
+
+@dataclass
+class Point:
+    x: int
+    y: int
+
+
+Line = Tuple[Point, Point]
+
+
+def solve(input: List[str]) -> int:
+    def parse_line(line: str) -> Line:
+        def parse_point(point: str) -> Point:
+            x, y = map(int, point.split(","))
+            return Point(x, y)
+
+        p1, p2 = map(parse_point, line.split(" -> "))
+        return (p1, p2)
+
+    def line_to_points(line: Line) -> Iterable[Point]:
+        def inclusive_range_any_order(a: int, b: int) -> Iterable[int]:
+            if a < b:
+                yield from range(a, b + 1)
+            else:
+                yield from range(a, b - 1, -1)
+
+        p1, p2 = line
+
+        xs = inclusive_range_any_order(p1.x, p2.x)
+        ys = inclusive_range_any_order(p1.y, p2.y)
+
+        if p1.x == p2.x:
+            xs = itertools.repeat(p1.x)
+
+        if p1.y == p2.y:
+            ys = itertools.repeat(p1.y)
+
+        yield from zip(xs, ys)
+
+    lines = list(map(parse_line, input))
+    counts = Counter(itertools.chain.from_iterable(line_to_points(l) for l in lines))
+
+    return sum(counts[p] > 1 for p in counts)
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d05/ex2/input
+++ b/2021/d05/ex2/input
@ -0,0 +1,500 @@
+284,294 -> 733,743
+625,347 -> 653,375
+561,848 -> 561,181
+836,102 -> 836,339
+946,941 -> 22,17
+18,954 -> 956,16
+370,142 -> 370,700
+990,966 -> 677,966
+366,603 -> 366,465
+728,942 -> 57,271
+615,493 -> 847,493
+584,281 -> 301,281
+125,356 -> 301,180
+941,569 -> 555,183
+151,116 -> 509,116
+41,18 -> 841,818
+627,670 -> 627,630
+965,472 -> 965,100
+93,404 -> 330,641
+475,963 -> 475,514
+389,389 -> 389,326
+842,565 -> 842,576
+454,700 -> 650,700
+73,810 -> 73,319
+450,212 -> 450,284
+316,392 -> 316,697
+915,592 -> 578,592
+622,485 -> 434,485
+109,853 -> 952,10
+305,73 -> 305,222
+27,489 -> 157,489
+191,979 -> 867,979
+527,329 -> 527,292
+301,645 -> 301,162
+639,730 -> 176,730
+46,964 -> 46,458
+727,422 -> 435,714
+28,552 -> 404,552
+33,108 -> 33,21
+227,249 -> 327,249
+414,903 -> 784,903
+69,422 -> 888,422
+422,924 -> 103,605
+793,353 -> 450,10
+714,682 -> 714,972
+201,745 -> 410,745
+408,713 -> 408,847
+174,842 -> 818,198
+863,353 -> 775,353
+199,780 -> 670,780
+877,947 -> 340,410
+163,202 -> 163,91
+955,919 -> 955,585
+836,271 -> 533,271
+258,366 -> 728,836
+582,749 -> 582,12
+80,40 -> 80,704
+287,213 -> 287,635
+390,546 -> 390,194
+837,511 -> 538,810
+473,281 -> 902,281
+851,865 -> 731,745
+918,59 -> 445,532
+796,215 -> 796,248
+875,111 -> 604,111
+660,805 -> 538,805
+507,850 -> 145,850
+585,861 -> 585,52
+426,74 -> 700,348
+206,405 -> 529,405
+418,333 -> 418,17
+368,457 -> 33,792
+186,81 -> 957,852
+505,283 -> 113,283
+20,878 -> 462,878
+750,237 -> 69,918
+15,280 -> 358,623
+798,981 -> 500,683
+965,970 -> 22,970
+950,970 -> 148,970
+660,392 -> 660,884
+862,405 -> 862,527
+801,283 -> 801,361
+71,837 -> 136,837
+651,438 -> 945,144
+524,607 -> 614,517
+348,955 -> 138,955
+957,164 -> 404,717
+531,581 -> 454,504
+710,185 -> 710,271
+822,86 -> 822,966
+745,233 -> 490,488
+350,823 -> 663,823
+824,67 -> 447,444
+846,667 -> 796,617
+666,24 -> 666,906
+640,39 -> 640,145
+654,481 -> 985,481
+581,894 -> 416,729
+443,11 -> 697,11
+318,627 -> 799,146
+113,78 -> 891,856
+181,149 -> 179,151
+451,74 -> 451,262
+458,726 -> 314,726
+218,662 -> 533,662
+965,108 -> 527,108
+782,481 -> 896,367
+557,927 -> 557,938
+506,242 -> 941,677
+948,778 -> 948,629
+567,816 -> 567,956
+323,773 -> 323,364
+864,980 -> 864,12
+611,699 -> 611,886
+613,392 -> 901,104
+528,905 -> 156,905
+632,206 -> 798,40
+338,237 -> 919,818
+256,889 -> 11,644
+835,52 -> 55,832
+464,144 -> 322,144
+254,747 -> 254,509
+866,892 -> 866,916
+827,946 -> 30,149
+899,84 -> 177,806
+134,634 -> 357,634
+781,492 -> 244,492
+817,762 -> 817,976
+818,749 -> 818,860
+262,480 -> 263,480
+409,576 -> 409,698
+242,151 -> 981,890
+149,519 -> 149,557
+42,990 -> 42,930
+687,974 -> 50,337
+758,382 -> 465,382
+760,861 -> 760,934
+17,835 -> 17,915
+645,923 -> 645,648
+702,116 -> 72,746
+153,162 -> 955,964
+185,101 -> 918,834
+554,179 -> 554,353
+879,673 -> 879,949
+368,13 -> 368,512
+582,105 -> 591,114
+146,291 -> 600,745
+609,538 -> 930,538
+320,604 -> 320,146
+566,698 -> 443,575
+167,708 -> 844,31
+712,630 -> 712,421
+912,930 -> 64,82
+980,931 -> 87,38
+23,893 -> 888,28
+640,435 -> 676,435
+701,516 -> 190,516
+684,145 -> 62,767
+127,471 -> 91,435
+685,197 -> 78,197
+103,493 -> 103,522
+309,986 -> 309,850
+938,270 -> 938,300
+295,72 -> 354,72
+948,889 -> 948,455
+254,733 -> 254,175
+95,329 -> 942,329
+19,672 -> 19,445
+206,807 -> 206,934
+886,961 -> 886,690
+117,386 -> 117,292
+199,59 -> 668,528
+299,263 -> 299,878
+28,295 -> 638,905
+10,140 -> 276,406
+279,526 -> 921,526
+485,128 -> 856,499
+418,398 -> 186,398
+296,577 -> 296,521
+514,261 -> 10,765
+691,673 -> 776,758
+131,430 -> 152,430
+858,85 -> 62,85
+394,846 -> 270,970
+827,913 -> 827,376
+634,669 -> 910,669
+12,53 -> 945,986
+782,467 -> 782,421
+159,832 -> 109,832
+793,807 -> 79,93
+120,584 -> 356,584
+645,16 -> 645,355
+526,685 -> 217,376
+296,305 -> 296,929
+954,144 -> 954,839
+748,88 -> 103,733
+523,804 -> 473,754
+524,316 -> 524,756
+696,183 -> 912,183
+288,564 -> 55,797
+568,103 -> 568,348
+468,626 -> 682,412
+163,163 -> 961,961
+762,824 -> 27,89
+623,625 -> 32,34
+865,343 -> 490,718
+259,458 -> 259,33
+944,660 -> 944,176
+781,804 -> 826,759
+15,702 -> 15,553
+403,310 -> 918,825
+438,734 -> 835,734
+825,13 -> 825,245
+129,611 -> 370,611
+49,939 -> 172,939
+687,906 -> 687,532
+629,482 -> 273,126
+727,218 -> 424,218
+447,451 -> 233,451
+142,779 -> 813,779
+527,27 -> 527,804
+482,55 -> 482,200
+39,264 -> 806,264
+884,636 -> 458,636
+467,121 -> 199,389
+856,925 -> 856,666
+666,359 -> 378,359
+11,946 -> 705,946
+491,281 -> 940,730
+86,112 -> 918,944
+974,807 -> 974,707
+445,67 -> 914,536
+953,394 -> 953,822
+468,398 -> 157,87
+231,620 -> 231,646
+979,869 -> 979,911
+450,330 -> 450,79
+675,659 -> 617,659
+66,181 -> 66,723
+181,406 -> 181,192
+908,334 -> 908,526
+254,891 -> 282,891
+777,791 -> 127,141
+469,58 -> 694,58
+954,957 -> 566,569
+957,957 -> 123,123
+741,359 -> 741,986
+763,526 -> 763,101
+857,427 -> 600,170
+527,756 -> 490,719
+625,249 -> 397,249
+798,702 -> 712,702
+868,75 -> 868,853
+332,296 -> 332,629
+211,829 -> 100,940
+12,139 -> 12,218
+655,978 -> 655,242
+99,852 -> 855,96
+486,267 -> 486,855
+474,90 -> 474,244
+948,491 -> 186,491
+896,59 -> 278,677
+295,732 -> 629,732
+860,936 -> 860,556
+143,790 -> 143,26
+371,847 -> 395,847
+739,301 -> 739,44
+384,716 -> 748,716
+848,423 -> 848,923
+855,23 -> 218,660
+381,805 -> 381,438
+451,610 -> 91,610
+906,957 -> 191,957
+118,675 -> 169,675
+836,818 -> 95,818
+368,945 -> 825,488
+165,299 -> 899,299
+392,327 -> 926,861
+663,16 -> 131,548
+630,302 -> 888,302
+206,869 -> 206,331
+979,413 -> 979,204
+894,860 -> 62,28
+444,897 -> 962,379
+550,158 -> 550,885
+845,736 -> 811,736
+846,857 -> 12,857
+981,730 -> 981,154
+694,835 -> 88,835
+21,101 -> 21,385
+19,960 -> 964,15
+283,721 -> 450,721
+59,136 -> 758,835
+287,313 -> 719,313
+471,252 -> 849,630
+682,189 -> 168,189
+10,921 -> 774,157
+884,598 -> 884,540
+207,615 -> 207,443
+627,408 -> 67,408
+285,36 -> 285,792
+116,585 -> 254,585
+183,86 -> 183,702
+220,138 -> 868,138
+833,68 -> 286,615
+367,534 -> 766,534
+907,514 -> 621,228
+133,593 -> 133,581
+164,727 -> 768,123
+566,227 -> 566,555
+983,988 -> 105,110
+620,177 -> 620,821
+612,413 -> 612,176
+168,889 -> 168,210
+871,487 -> 559,175
+399,870 -> 761,870
+236,976 -> 582,630
+699,216 -> 699,887
+153,745 -> 790,745
+444,749 -> 444,257
+808,165 -> 939,165
+546,525 -> 95,976
+583,179 -> 373,389
+235,816 -> 840,816
+744,89 -> 832,89
+425,317 -> 465,357
+267,235 -> 114,82
+887,59 -> 572,374
+808,237 -> 808,626
+431,352 -> 400,383
+815,376 -> 815,905
+249,218 -> 989,958
+120,435 -> 357,198
+807,551 -> 490,234
+910,524 -> 910,725
+802,304 -> 447,659
+789,228 -> 678,339
+229,322 -> 52,322
+658,393 -> 506,393
+378,438 -> 378,569
+163,981 -> 473,671
+537,984 -> 935,586
+58,945 -> 966,37
+132,696 -> 565,263
+136,813 -> 136,284
+606,656 -> 298,348
+533,572 -> 673,712
+872,912 -> 301,341
+16,287 -> 16,613
+571,541 -> 980,950
+117,495 -> 35,495
+85,79 -> 682,676
+425,431 -> 117,739
+982,984 -> 10,12
+28,75 -> 431,478
+259,529 -> 259,436
+762,267 -> 170,859
+323,135 -> 929,741
+81,238 -> 561,718
+128,213 -> 876,961
+649,466 -> 649,540
+715,863 -> 119,863
+830,624 -> 794,660
+123,968 -> 977,114
+489,466 -> 489,811
+27,10 -> 980,963
+255,732 -> 255,484
+574,829 -> 431,829
+548,743 -> 22,217
+903,297 -> 903,763
+684,774 -> 64,154
+260,823 -> 683,823
+422,211 -> 422,826
+10,196 -> 988,196
+108,802 -> 15,802
+104,70 -> 104,452
+885,59 -> 885,36
+68,854 -> 68,774
+731,935 -> 731,718
+657,986 -> 617,986
+732,292 -> 732,32
+841,56 -> 841,83
+74,108 -> 862,896
+654,895 -> 323,895
+374,952 -> 374,217
+90,723 -> 750,63
+246,89 -> 911,754
+453,301 -> 755,301
+983,988 -> 23,28
+81,705 -> 133,757
+752,743 -> 752,397
+53,243 -> 449,639
+451,811 -> 451,187
+26,672 -> 26,699
+254,861 -> 943,861
+643,740 -> 643,966
+486,655 -> 149,318
+375,146 -> 375,973
+76,293 -> 103,293
+246,398 -> 246,248
+324,392 -> 595,121
+130,577 -> 131,577
+380,623 -> 549,454
+224,181 -> 985,942
+310,223 -> 310,594
+23,982 -> 23,738
+19,858 -> 832,858
+726,531 -> 726,578
+730,433 -> 196,433
+606,599 -> 242,599
+444,832 -> 444,238
+198,870 -> 47,870
+944,473 -> 795,473
+737,386 -> 178,945
+328,902 -> 328,644
+422,851 -> 567,851
+674,781 -> 215,781
+920,757 -> 302,757
+225,932 -> 640,517
+359,337 -> 791,337
+935,430 -> 935,262
+772,850 -> 280,358
+175,829 -> 175,451
+938,204 -> 234,908
+253,749 -> 308,749
+704,458 -> 468,458
+222,95 -> 743,616
+968,840 -> 123,840
+491,619 -> 491,889
+979,580 -> 979,459
+901,193 -> 171,923
+246,155 -> 246,680
+711,755 -> 247,755
+671,734 -> 475,734
+803,783 -> 129,109
+145,890 -> 920,115
+463,521 -> 463,700
+782,99 -> 782,311
+547,467 -> 630,467
+14,88 -> 795,869
+653,899 -> 653,90
+488,874 -> 488,570
+93,879 -> 645,327
+320,658 -> 40,938
+611,246 -> 611,22
+258,935 -> 258,829
+931,436 -> 931,263
+252,460 -> 252,461
+490,382 -> 965,382
+242,89 -> 242,617
+271,111 -> 595,435
+462,706 -> 242,486
+557,328 -> 747,328
+486,99 -> 486,333
+156,40 -> 488,372
+323,482 -> 138,297
+595,539 -> 812,756
+923,861 -> 377,315
+934,952 -> 256,274
+314,777 -> 314,12
+508,47 -> 508,144
+888,807 -> 701,807
+745,774 -> 878,907
+740,716 -> 740,215
+62,43 -> 62,12
+571,196 -> 454,196
+568,107 -> 408,107
+549,676 -> 404,676
+595,573 -> 595,970
+148,168 -> 193,123
+763,71 -> 759,71
+797,64 -> 307,64
+959,984 -> 32,57
+457,562 -> 634,562
+127,521 -> 601,47
+112,296 -> 112,120
+148,755 -> 451,755
+636,494 -> 870,494
+910,242 -> 945,277
+912,911 -> 912,892
+759,815 -> 759,314
+391,285 -> 391,959
+455,460 -> 182,460
+112,78 -> 112,385
+842,179 -> 842,592
+236,424 -> 421,424
+508,907 -> 30,907
+637,219 -> 34,822
+503,375 -> 503,205
+570,533 -> 626,533
+658,11 -> 658,94
+179,286 -> 326,433
+918,214 -> 200,932
+339,887 -> 81,887
+794,91 -> 50,835
+225,356 -> 225,261
+80,160 -> 80,335
+148,64 -> 847,763
+595,393 -> 941,393
--- a/2021/d06/ex1/ex1.py
+++ b/2021/d06/ex1/ex1.py
@ -0,0 +1,43 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from collections import Counter
+from dataclasses import dataclass
+from typing import Iterator, List
+
+
+def nth(iterable: Iterator[int], n: int) -> int:
+    return next(itertools.islice(iterable, n, None))
+
+
+def solve(input: List[str]) -> int:
+    fish = [0] * 9
+    for n, count in Counter(map(int, input[0].split(","))).items():
+        fish[n] = count
+
+    def step(fish: List[int]) -> List[int]:
+        # Count how many clones happen
+        new_fish = fish[0]
+
+        # Do the next cycle
+        fish[0:-1] = fish[1:]
+        fish[6] += new_fish
+        fish[8] = new_fish  # Override number of new fish
+
+        return fish
+
+    def iter(fish: List[int]) -> Iterator[List[int]]:
+        while True:
+            yield (fish := step(fish))
+
+    return sum(nth(iter(fish), 80 - 1))
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d06/ex1/input
+++ b/2021/d06/ex1/input
@ -0,0 +1 @@
+3,1,4,2,1,1,1,1,1,1,1,4,1,4,1,2,1,1,2,1,3,4,5,1,1,4,1,3,3,1,1,1,1,3,3,1,3,3,1,5,5,1,1,3,1,1,2,1,1,1,3,1,4,3,2,1,4,3,3,1,1,1,1,5,1,4,1,1,1,4,1,4,4,1,5,1,1,4,5,1,1,2,1,1,1,4,1,2,1,1,1,1,1,1,5,1,3,1,1,4,4,1,1,5,1,2,1,1,1,1,5,1,3,1,1,1,2,2,1,4,1,3,1,4,1,2,1,1,1,1,1,3,2,5,4,4,1,3,2,1,4,1,3,1,1,1,2,1,1,5,1,2,1,1,1,2,1,4,3,1,1,1,4,1,1,1,1,1,2,2,1,1,5,1,1,3,1,2,5,5,1,4,1,1,1,1,1,2,1,1,1,1,4,5,1,1,1,1,1,1,1,1,1,3,4,4,1,1,4,1,3,4,1,5,4,2,5,1,2,1,1,1,1,1,1,4,3,2,1,1,3,2,5,2,5,5,1,3,1,2,1,1,1,1,1,1,1,1,1,3,1,1,1,3,1,4,1,4,2,1,3,4,1,1,1,2,3,1,1,1,4,1,2,5,1,2,1,5,1,1,2,1,2,1,1,1,1,4,3,4,1,5,5,4,1,1,5,2,1,3
--- a/2021/d06/ex2/ex2.py
+++ b/2021/d06/ex2/ex2.py
@ -0,0 +1,43 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from collections import Counter
+from dataclasses import dataclass
+from typing import Iterator, List
+
+
+def nth(iterable: Iterator[int], n: int) -> int:
+    return next(itertools.islice(iterable, n, None))
+
+
+def solve(input: List[str]) -> int:
+    fish = [0] * 9
+    for n, count in Counter(map(int, input[0].split(","))).items():
+        fish[n] = count
+
+    def step(fish: List[int]) -> List[int]:
+        # Count how many clones happen
+        new_fish = fish[0]
+
+        # Do the next cycle
+        fish[0:-1] = fish[1:]
+        fish[6] += new_fish
+        fish[8] = new_fish  # Override number of new fish
+
+        return fish
+
+    def iter(fish: List[int]) -> Iterator[List[int]]:
+        while True:
+            yield (fish := step(fish))
+
+    return sum(nth(iter(fish), 256 - 1))
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d06/ex2/input
+++ b/2021/d06/ex2/input
@ -0,0 +1 @@
+3,1,4,2,1,1,1,1,1,1,1,4,1,4,1,2,1,1,2,1,3,4,5,1,1,4,1,3,3,1,1,1,1,3,3,1,3,3,1,5,5,1,1,3,1,1,2,1,1,1,3,1,4,3,2,1,4,3,3,1,1,1,1,5,1,4,1,1,1,4,1,4,4,1,5,1,1,4,5,1,1,2,1,1,1,4,1,2,1,1,1,1,1,1,5,1,3,1,1,4,4,1,1,5,1,2,1,1,1,1,5,1,3,1,1,1,2,2,1,4,1,3,1,4,1,2,1,1,1,1,1,3,2,5,4,4,1,3,2,1,4,1,3,1,1,1,2,1,1,5,1,2,1,1,1,2,1,4,3,1,1,1,4,1,1,1,1,1,2,2,1,1,5,1,1,3,1,2,5,5,1,4,1,1,1,1,1,2,1,1,1,1,4,5,1,1,1,1,1,1,1,1,1,3,4,4,1,1,4,1,3,4,1,5,4,2,5,1,2,1,1,1,1,1,1,4,3,2,1,1,3,2,5,2,5,5,1,3,1,2,1,1,1,1,1,1,1,1,1,3,1,1,1,3,1,4,1,4,2,1,3,4,1,1,1,2,3,1,1,1,4,1,2,5,1,2,1,5,1,1,2,1,2,1,1,1,1,4,3,4,1,5,5,4,1,1,5,2,1,3
--- a/2021/d07/ex1/ex1.py
+++ b/2021/d07/ex1/ex1.py
@ -0,0 +1,21 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from typing import List
+
+
+def solve(input: List[str]) -> int:
+    nums = sorted(int(n) for n in input[0].split(","))
+    median = nums[len(nums) // 2]
+
+    return sum(abs(n - median) for n in nums)
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d07/ex1/input
+++ b/2021/d07/ex1/input
@ -0,0 +1 @@
+1101,1,29,67,1102,0,1,65,1008,65,35,66,1005,66,28,1,67,65,20,4,0,1001,65,1,65,1106,0,8,99,35,67,101,99,105,32,110,39,101,115,116,32,112,97,115,32,117,110,101,32,105,110,116,99,111,100,101,32,112,114,111,103,114,97,109,10,1133,1029,1446,1005,596,277,439,544,201,317,237,33,252,774,482,291,57,1434,153,134,385,993,677,1189,99,1082,351,80,1563,195,581,693,5,633,184,552,11,606,462,48,134,1451,850,221,336,661,276,156,932,23,98,76,327,212,489,230,819,998,1037,1561,206,159,757,207,1203,224,1459,294,39,1108,96,89,1664,353,41,83,942,771,362,193,900,676,851,277,558,368,1054,316,143,464,85,896,558,52,669,163,696,140,340,542,817,783,1436,786,81,21,669,184,430,312,1500,797,698,611,314,145,125,391,785,867,488,144,9,967,560,245,116,96,1769,314,533,25,0,1375,1307,1273,1178,332,59,26,234,487,480,615,313,629,28,707,96,637,30,350,1286,900,777,115,56,79,809,1101,13,150,741,940,20,403,384,479,622,108,325,276,609,654,535,539,62,187,414,535,140,222,845,357,55,17,8,1430,853,759,331,673,202,482,1280,714,911,409,429,604,278,478,301,408,590,329,1482,110,423,488,7,628,66,196,399,86,241,1058,501,1284,594,710,799,34,60,668,457,0,1209,20,50,1134,288,415,399,86,540,1356,285,1541,172,3,634,1387,146,669,195,403,601,758,160,970,760,43,213,68,805,50,350,292,78,252,54,1021,882,241,808,601,892,878,1401,48,191,74,1429,94,520,505,679,1133,120,485,183,362,684,520,1366,301,123,290,1248,140,44,230,572,57,1101,217,906,1012,668,85,230,32,100,472,275,78,91,19,61,732,518,189,85,1531,1255,134,489,637,792,42,36,392,603,976,651,127,486,340,534,185,890,346,906,1295,319,321,597,252,183,554,124,44,426,131,408,582,429,645,1227,574,14,1828,359,184,1830,10,288,194,949,1578,492,502,149,609,77,92,320,233,1026,123,26,188,1123,4,665,1793,331,858,481,197,424,133,933,338,7,163,1269,665,19,1,538,126,895,1751,345,895,203,175,66,305,1479,239,718,386,8,1148,203,636,1211,635,149,489,1156,1828,61,328,331,287,262,8,3,522,1427,931,1103,199,329,930,779,124,446,391,903,696,1764,16,595,522,143,296,19,872,29,546,566,256,63,1195,862,516,267,452,1287,11,547,760,77,117,988,185,293,421,118,767,70,169,456,600,755,740,1799,97,507,1165,265,1126,376,1250,408,22,674,774,361,54,558,1021,529,29,871,527,474,218,47,309,61,188,1365,725,267,235,359,1004,1771,765,8,17,103,89,967,65,302,759,1688,882,709,1469,123,548,834,355,646,404,76,257,101,627,2,66,1328,137,42,23,127,110,632,683,1163,843,1119,16,497,1756,347,958,981,57,185,204,1403,530,536,104,68,1152,95,320,959,144,281,350,622,717,112,631,150,19,938,296,1272,825,37,192,350,847,306,824,1042,320,480,857,589,137,687,93,21,1601,547,550,491,161,49,124,292,396,34,24,95,932,56,968,197,109,1300,1326,605,357,412,14,179,450,991,173,120,1402,478,77,933,88,96,49,95,596,1885,841,441,659,309,418,87,134,34,815,759,631,209,728,7,232,1304,698,140,304,1448,101,1,239,1321,362,1367,1411,279,111,633,1347,110,18,710,443,1676,64,531,386,64,518,619,893,140,301,426,1451,261,1083,115,61,943,60,891,217,475,48,436,586,31,287,196,430,357,78,161,1533,745,198,715,8,307,225,604,263,992,371,749,700,1573,573,546,480,425,47,88,66,799,388,60,736,111,81,856,29,695,141,4,271,143,939,423,3,1260,265,24,903,292,23,80,196,1245,399,123,3,532,283,366,1175,187,15,450,487,117,1041,669,59,579,159,461,598,915,666,1231,999,253,185,1016,135,1317,253,111,1261,833,26,851,120,11,63,718,682,233,76,0,50,1678,777,286,279,90,47,158,71,35,475,245,550,4,942,1816,1646,102,175,343,12,446,12,623,44,157,10,555,1173,651,361,745,1870,97,237,1628,90,233,126,1596,1146,746,383,209,55,209,318,904,144,90,21,86,4,970,262,8,210,249,871,1216,1003,172,405,821,225,2,143,915,129,598,397,583,1400,315,113,33,75,426,2,611,293,196,419,125,176,496,4,607,1425,27,48,172,972,626,227,184,1257,514,209,524,22,58,927,4,931,3,6,104,716,961,17,4,154,249,558,203,180,180,1194,935,263,535,380,1439,274,1566,873,1763,2,89,636,407,667,438,966,757,245,730,328,915,167,245,126,52,652,938,1183,320,1298,10,844,36,263,382,37,142
--- a/2021/d07/ex2/ex2.py
+++ b/2021/d07/ex2/ex2.py
@ -0,0 +1,28 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from math import ceil, floor
+from typing import List
+
+
+def solve(input: List[str]) -> int:
+    def fuel(dist: int) -> int:
+        return dist * (dist + 1) // 2
+
+    nums = list(int(n) for n in input[0].split(","))
+    mean = sum(nums) / len(nums)
+
+    upper = sum(fuel(abs(n - ceil(mean))) for n in nums)
+    lower = sum(fuel(abs(n - floor(mean))) for n in nums)
+
+    return min(upper, lower)
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d07/ex2/input
+++ b/2021/d07/ex2/input
@ -0,0 +1 @@
+1101,1,29,67,1102,0,1,65,1008,65,35,66,1005,66,28,1,67,65,20,4,0,1001,65,1,65,1106,0,8,99,35,67,101,99,105,32,110,39,101,115,116,32,112,97,115,32,117,110,101,32,105,110,116,99,111,100,101,32,112,114,111,103,114,97,109,10,1133,1029,1446,1005,596,277,439,544,201,317,237,33,252,774,482,291,57,1434,153,134,385,993,677,1189,99,1082,351,80,1563,195,581,693,5,633,184,552,11,606,462,48,134,1451,850,221,336,661,276,156,932,23,98,76,327,212,489,230,819,998,1037,1561,206,159,757,207,1203,224,1459,294,39,1108,96,89,1664,353,41,83,942,771,362,193,900,676,851,277,558,368,1054,316,143,464,85,896,558,52,669,163,696,140,340,542,817,783,1436,786,81,21,669,184,430,312,1500,797,698,611,314,145,125,391,785,867,488,144,9,967,560,245,116,96,1769,314,533,25,0,1375,1307,1273,1178,332,59,26,234,487,480,615,313,629,28,707,96,637,30,350,1286,900,777,115,56,79,809,1101,13,150,741,940,20,403,384,479,622,108,325,276,609,654,535,539,62,187,414,535,140,222,845,357,55,17,8,1430,853,759,331,673,202,482,1280,714,911,409,429,604,278,478,301,408,590,329,1482,110,423,488,7,628,66,196,399,86,241,1058,501,1284,594,710,799,34,60,668,457,0,1209,20,50,1134,288,415,399,86,540,1356,285,1541,172,3,634,1387,146,669,195,403,601,758,160,970,760,43,213,68,805,50,350,292,78,252,54,1021,882,241,808,601,892,878,1401,48,191,74,1429,94,520,505,679,1133,120,485,183,362,684,520,1366,301,123,290,1248,140,44,230,572,57,1101,217,906,1012,668,85,230,32,100,472,275,78,91,19,61,732,518,189,85,1531,1255,134,489,637,792,42,36,392,603,976,651,127,486,340,534,185,890,346,906,1295,319,321,597,252,183,554,124,44,426,131,408,582,429,645,1227,574,14,1828,359,184,1830,10,288,194,949,1578,492,502,149,609,77,92,320,233,1026,123,26,188,1123,4,665,1793,331,858,481,197,424,133,933,338,7,163,1269,665,19,1,538,126,895,1751,345,895,203,175,66,305,1479,239,718,386,8,1148,203,636,1211,635,149,489,1156,1828,61,328,331,287,262,8,3,522,1427,931,1103,199,329,930,779,124,446,391,903,696,1764,16,595,522,143,296,19,872,29,546,566,256,63,1195,862,516,267,452,1287,11,547,760,77,117,988,185,293,421,118,767,70,169,456,600,755,740,1799,97,507,1165,265,1126,376,1250,408,22,674,774,361,54,558,1021,529,29,871,527,474,218,47,309,61,188,1365,725,267,235,359,1004,1771,765,8,17,103,89,967,65,302,759,1688,882,709,1469,123,548,834,355,646,404,76,257,101,627,2,66,1328,137,42,23,127,110,632,683,1163,843,1119,16,497,1756,347,958,981,57,185,204,1403,530,536,104,68,1152,95,320,959,144,281,350,622,717,112,631,150,19,938,296,1272,825,37,192,350,847,306,824,1042,320,480,857,589,137,687,93,21,1601,547,550,491,161,49,124,292,396,34,24,95,932,56,968,197,109,1300,1326,605,357,412,14,179,450,991,173,120,1402,478,77,933,88,96,49,95,596,1885,841,441,659,309,418,87,134,34,815,759,631,209,728,7,232,1304,698,140,304,1448,101,1,239,1321,362,1367,1411,279,111,633,1347,110,18,710,443,1676,64,531,386,64,518,619,893,140,301,426,1451,261,1083,115,61,943,60,891,217,475,48,436,586,31,287,196,430,357,78,161,1533,745,198,715,8,307,225,604,263,992,371,749,700,1573,573,546,480,425,47,88,66,799,388,60,736,111,81,856,29,695,141,4,271,143,939,423,3,1260,265,24,903,292,23,80,196,1245,399,123,3,532,283,366,1175,187,15,450,487,117,1041,669,59,579,159,461,598,915,666,1231,999,253,185,1016,135,1317,253,111,1261,833,26,851,120,11,63,718,682,233,76,0,50,1678,777,286,279,90,47,158,71,35,475,245,550,4,942,1816,1646,102,175,343,12,446,12,623,44,157,10,555,1173,651,361,745,1870,97,237,1628,90,233,126,1596,1146,746,383,209,55,209,318,904,144,90,21,86,4,970,262,8,210,249,871,1216,1003,172,405,821,225,2,143,915,129,598,397,583,1400,315,113,33,75,426,2,611,293,196,419,125,176,496,4,607,1425,27,48,172,972,626,227,184,1257,514,209,524,22,58,927,4,931,3,6,104,716,961,17,4,154,249,558,203,180,180,1194,935,263,535,380,1439,274,1566,873,1763,2,89,636,407,667,438,966,757,245,730,328,915,167,245,126,52,652,938,1183,320,1298,10,844,36,263,382,37,142
--- a/2021/d08/ex1/ex1.py
+++ b/2021/d08/ex1/ex1.py
@ -0,0 +1,38 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from dataclasses import dataclass
+from typing import List, Set
+
+
+@dataclass
+class Entry:
+    signals: List[Set[str]]
+    outputs: List[Set[str]]
+
+
+def solve(input: List[str]) -> int:
+    def parse_entry(input: str) -> Entry:
+        signals, outputs = input.split(" | ")
+        return Entry(
+            [set(s) for s in signals.split()], [set(o) for o in outputs.split()]
+        )
+
+    entries = [parse_entry(line) for line in input]
+
+    return sum(
+        itertools.chain.from_iterable(
+            map(lambda __: 1, filter(lambda d: len(d) in (2, 3, 4, 7), entry.outputs))
+            for entry in entries
+        )
+    )
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d08/ex1/input
+++ b/2021/d08/ex1/input
@ -0,0 +1,200 @@
+badc bd dbeaf cfdbge dfb cfbdea efbag edcfgab dcafe degfca | eacfd acdfbe cbdegf fcbaedg
+cd fdbac egcfab gbadcfe cfgdeb cbadfe deca cdf dfabg abefc | dcf cfbad gbafced fcd
+cg agecfb cbg eabgfdc egdc fdgba bafecd cbdfe bfcdeg cfgdb | efdcb adcfeb fbdcg gbc
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+bae adcgfbe cdfeag ab dcgeb bfdage agecb cagfe abcf bfcaeg | bae aeb agfceb afceg
+ae adefcb gaceb gadceb edag efadcgb badgc cfgbe cadbfg cea | ceabgd fbeacdg aged aged
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+ag cdeafg gdbfce daceb acgf efgbda adg cegda gaedbfc efcgd | debac eadbc bgaecdf cgbaedf
+acefdbg debgac ecdgf ead facebg eafgb ad fedbga bfda eafgd | adbf eagfd eabcfgd ecagfb
+cd bafegc fgcaed fcaeg dgc fdcag agdbf fedc gbadce egdabcf | fedbcga bgafd fcde cfed
+decg egf ecgbfa degfa edbagfc dgcabf cdfag eg fcaedg faebd | gcadef efadg egf eg
+feacbg cgfadbe efb efbga dfagb eb aefgc bgec cgedaf dcebfa | eb be be fbe
+begc eacfdb dfacg agcfe ce eagbf eac eafdgb aefbcg dfgaecb | ce ce ce gbce
+dfeagb dgaeb dbagefc gbcfae degf decba cbgdfa bgfda eg gae | ge agfdcbe bdace fdeg
+cgdab cegdbf cfbad bg aegb caedfg eacgbfd dgb dgaec gdbaec | gbea eacgd gb cgaebd
+ag ecdgbaf edcba eagcd aeg gcfa dfcgae egcdf gfdeba fcgbde | fgeadb dacge fdagceb egafbd
+fdbgec bge fdacbe bfdga edfgb cbgaed gefc cefdb ge baegdfc | ebfgd gbe begdf eg
+cedafb gdab fgced cabdf fgbaecd dcbgf gb bgc gabfdc ebfgca | bcadgf cbfda cdgfab agdb
+fdcbg bgface ecdabf ad fgcbaed gcefad dac efgac cfagd daeg | dcfabge edga ad gcfea
+bce gaecdb aefc bedfgca acbfge aebgf fbceg defgba dgfcb ce | ceaf ce bfgce ce
+gefadc gefadb agd ebfcdag dbeg dfagb abfed gafcb dg adbcef | fbgad bged gd cfebda
+dcfge egdbf adcgf bafecgd ecd gdfeac bdecaf ec cfgdab cage | acge dacgf facdg cgea
+bagdec gecdfba gdabe deb eabc be acdgfe afgdb deagc gdecfb | aebgd cgdea adbge eabc
+gebca bedgaf ac gcbeaf bcagedf bafge egcfda bedgc cabf cea | ecbdg efcgab ebagc bgadfec
+edacbg gcfad efdabg bc cgfdbae bdc cfedab efbc beadf fadbc | dbc fcbe fbedacg cabfd
+adfgce acgfb bgfadc dgbca fc gfc fgacdbe fagbe bcdf ebagcd | cbagdfe gfc fgbac cgbaed
+gdbfec bea acdb ba bcged edabgc gcfaebd afebcg gedba gdeaf | ba fgcebd efgda gadfecb
+gd gcda bgd gafbcde bdcfag bcgdf cedfb bgefda eacfbg cfbga | fgcab fdgcba bgacf bfedga
+fgcadeb abdgc gce bagec fcbea ge aebcgd gead cedfgb bagdfc | gbdace baefc fdcagb cdgab
+fbca aedfcg eagcbd fadbec bdgef fec cf bgcfade dbcef cbade | fgedb bgefadc fc cf
+dbgfa feca gfbced cf abfgce fcb cafbg eabgc acdbge edafcbg | abgdf dbcgef geabfc fcb
+dbaf fag bdfgea ecbgfa dgbfe fa edacg agcfdbe cefdbg fdgea | fgbaed cdegbf dacfbge gdcfbe
+abc acefbd gacedbf gbcde dgabf ca fgcedb cega dgbca cgeadb | ca bcged abgfd bca
+ceabgd cgfeb ea aedf gcbdfa cadbf acdfeb abfec eac dgcefba | cgdbafe cea adfe aec
+dbcfgae agebc ebgd cebdfa ebacdg deagc be fdecga gbacf bce | deagcb agecdf caefdg cegad
+dcaeg gea gdaf befgac cefgd facbdeg dcgbfe ga dagfec adecb | gadf gaedc age cabedgf
+bead dagfbe gda bagfec ad egfba ecgfad fdcgb ecfabdg dfgab | agefdc dga bgfea dafcgbe
+abcgd gecbfda cegd badfge bcaed fcaeb ed adcgfb gcabed edb | acefb acbgde deb ed
+cgefdab dgbcfe gbe beca be fdecga bgcafe bfgda abgfe fgace | bfgda eb gbe bdgaf
+age cefbadg bcfea cdagbe begca ag gedfca cbfdeg ebcgd dbga | efbac ega fecab dgba
+cgedf fc defbgc cdf fceb dgebf bafgdce eadbgf ecgad gcfadb | cf deabgfc efgdbc fgbcda
+bdgeacf bagdef gb becg bcfage cafbg bga fdbac caefdg eafcg | bcedafg cbeg bg gb
+dfceb gcdab ecbad gfbdea eab gcbeda bgcdeaf ea abfgdc cgea | baedc egca dgacbe cedfb
+gdaeb dgfbc cefg fe cfbgaed gdfeb fadcbg defgcb abcdfe dfe | gdcfba eagdb fe cfeg
+abfcedg afgcde acgfd ae bdecga efbcd dea fdgabc feacd gfae | afdcge gaef aefgcd geacfd
+beadfg cfdgb fdb agfcbde db abcgfd ecdgf cbagf bafgce bdca | efgcd dcefg cdgfe bd
+fagbe fedbcag afbgcd agdfbe age adgcbe ea fead egbcf abgdf | gae cbegf afgdb ea
+badfcg fagdc gaf fedcgba dagb acefd dbgcf cgfdbe ag gbecfa | ag bagd bdfgca fbadgc
+cfebg gc fcbea dcbafe gbc gcedafb cegdba cagf fbgde baecgf | cg agcf befgc bgc
+fegb ecdaf ecb gacefdb eb gdacbf cdegba abgfc afceb acegfb | ebafgcd afdgceb ebc be
+adgb cgbae bg abecdg gcefa ecbad dbgfec gbe cbfdega baecfd | badg badg dbag aegbc
+ab bfa gbedcaf adbgfe bfecg acefb fgdcae bcad fceda ebafdc | gebdaf edcfag ab ba
+ceadbg cd gfdeca ebgfd gdfec dce fegbca ecfag fadc gdeabfc | gfaec gface fdac ecadgf
+fbagd egdafb bdg adcefg gbfac daegbcf eadgf bd bfde dgceab | dbfe bd agfde agdef
+ebg bgdfe acebdg dcfage abfdge agefd dgbcf eb bdfegac afbe | cdfbg aefb dcagef edfga
+bfcd efc bfdcge gbdec bagfe agdceb cf dacgbef bfgec eadgfc | cfe dcbf cgebdf dbecag
+cda cefdbg fgeca fdgbeca acgdf bdcgf da deafcb fbgcad bdga | afgbcd cfega gbfcda gdebcf
+dcaf cagfb gdacb bgdfca fgaecb ebdag cd fdgcbae dbc bcfegd | cfdegb dc abcgd cbfedag
+gabedc dgfab ecdfbg adegf afbc dbagc bacedgf bf fdb fdcbag | cfedgb dgcfab gbfcead dcbga
+bcagde efd bgfcd fdecb aefb fe dcfbae gacfebd caebd afecgd | ebcdf afeb ef befa
+abfc gcdaef agecdfb cb gacedb cgb gcbdf bdgfac gedfb gcdaf | gfceda bc bdfgaec bdgef
+geabc gcebad cgbeaf begdcf gfabe fe bfgda gfe afce ebcfagd | febgac fcea fbcged baecgd
+aedfb gbfe acbgde fe fcedgba aef fcadge bacdf fegdab ebdga | fcgdeba afdeb ef fae
+gbcfd adfgcb gba dgcbafe agbfde ag cfag fecdbg gbdac edcab | fgcbd bgcad agb bdefga
+agfde efgcba gaefc bdcfeg cfe bafc bgcedaf egbac agcedb cf | gebacf ecgafb gfceab cefag
+febdc begcd ecgbdf dbacfe bdfagc adgec gbd gb afbdceg gefb | dbg gacbfd egcdfb gfebcd
+decfbg dagfb afcgbd gdcfb cbaedf caefgdb da gdca gafeb abd | adbgcef dgafb abd cfbgeda
+begcfd bgeaf dcfaeb cadfeg gcdb cadbgfe cg ecfbd cfbge cgf | cg gfc gdcb gcf
+ecagdf dfcebg fgbea bg cbeadgf egb ebcafg edfab gbca fegac | bafeg aebfd gcab fbecdag
+dgacf abfecg fcgadeb cgd gdbace cgbfa egfda dbfc cdbfga dc | cfbd gabdce dbgcaf egfda
+afedcgb afge bfead gf gdfbe fgabed dgcbe dfceab dgf fabgdc | feag cdabef bgdacf gfea
+adebgc de bfgacde beafdg egabc egcabf deg cead cbdeg dcgfb | ed eabdgf eadc dbafge
+fcdbgae gbacf ebgdfc bcadeg bdgea fagdbe gce aecgb acde ce | cge ecg cabeg efdcgba
+aefgcb fedagcb cefbdg ef dcbeg bacdge fegd edbfc fabdc cef | ecbgfd gdef bacdeg bcdeg
+geadc gecfad gfcadb eg agdcf bgafce gdef acdbe gea dabegcf | ecfbag gebcaf baecd dfeg
+cdeba bd aegcd bfadec ecfab bafd agbfce bfdcge bdc cgebdfa | abcfe agdce db adecg
+fbadg faedgc bgdac bcegd bcadge agc gdefcb cbae gdfbace ca | defgcb ceagbd bdgca afedcg
+acgfd cbdage agcbd dfa edcfg fa dbcfeag fabc dbaefg gdbcfa | af gedabfc af ebgdfac
+dafgbc dfegc dc cgfae cgeafd cdf cagefb ceda bfged fdegcba | aecd cade deac fbged
+cbegda dgfeb gefcb aefbgc fdgceb agdfe dgb bd fdbc bdgfaec | dcgbeaf db gfbed efdag
+aefbd cdbeagf gd fdgc fgcdab afbcg bdg egfabc bfgad aebgcd | gdfc gadcfeb cfgd fgacb
+eb gcbaed aeb fgdecba begd eagdc cadfb eabdc cfgade gacfeb | egdca dcbea bdfcgea be
--- a/2021/d08/ex2/ex2.py
+++ b/2021/d08/ex2/ex2.py
@ -0,0 +1,78 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from dataclasses import dataclass
+from typing import Dict, List, Set
+
+
+@dataclass
+class Entry:
+    signals: List[Set[str]]
+    outputs: List[Set[str]]
+
+
+def solve(input: List[str]) -> int:
+    def parse_entry(input: str) -> Entry:
+        signals, outputs = input.split(" | ")
+        return Entry(
+            [set(s) for s in signals.split()], [set(o) for o in outputs.split()]
+        )
+
+    def deduce_signals(entry: Entry) -> Dict[int, str]:
+        _1, _7, _4, *signals_to_deduce, _8 = sorted(entry.signals, key=len)
+        signals = {
+            1: _1,
+            4: _4,
+            7: _7,
+            8: _8,
+        }
+
+        for sig in signals_to_deduce:
+            match = len(sig), len(sig & _4), len(sig & _1)
+
+            if match == (6, 3, 2):
+                signals[0] = sig
+            elif match == (5, 2, 1):
+                signals[2] = sig
+            elif match == (5, 3, 2):
+                signals[3] = sig
+            elif match == (5, 3, 1):
+                signals[5] = sig
+            elif match == (6, 3, 1):
+                signals[6] = sig
+            elif match == (6, 4, 2):
+                signals[9] = sig
+            else:
+                assert False  # Sanity check
+
+        assert len(signals) == 10  # Sanity check
+        return signals
+
+    def deduce_entry(entry: Entry) -> int:
+        decoded_signals = deduce_signals(entry)
+
+        res = 0
+
+        for output in entry.outputs:
+            assert output in decoded_signals.values()  # Sanity check
+
+            for n, signal in decoded_signals.items():
+                if output != signal:
+                    continue
+                res = res * 10 + n
+
+        return res
+
+    entries = [parse_entry(line) for line in input]
+
+    return sum(map(deduce_entry, entries))
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d08/ex2/input
+++ b/2021/d08/ex2/input
@ -0,0 +1,200 @@
+badc bd dbeaf cfdbge dfb cfbdea efbag edcfgab dcafe degfca | eacfd acdfbe cbdegf fcbaedg
+cd fdbac egcfab gbadcfe cfgdeb cbadfe deca cdf dfabg abefc | dcf cfbad gbafced fcd
+cg agecfb cbg eabgfdc egdc fdgba bafecd cbdfe bfcdeg cfgdb | efdcb adcfeb fbdcg gbc
+bfceg gfadb dbcfgea bgaef efad abe bcdgfa ea fbdgea agecbd | eadf ceadbg abfge fecdbga
+gdcafe eacb adc gbfda afdceb edgbcf badfc ecgbafd ac fdbce | ebfcd cefdab bdfgeca egbdacf
+aefbgd fbdc fbecg egdcb edcbag bf gcefa fbedcg bagfced fbg | afgce cfbd bdcf geafdbc
+ebgacd edacg gcdeaf cabfg dbc bd cdbgaef ebad fecgbd acbgd | dgbac db caegbdf gcbfa
+defbga gead ge efagcb gdafbc cegbdfa egf bfdce bgdef dgabf | gef eg bfcdag ge
+bae adcgfbe cdfeag ab dcgeb bfdage agecb cagfe abcf bfcaeg | bae aeb agfceb afceg
+ae adefcb gaceb gadceb edag efadcgb badgc cfgbe cadbfg cea | ceabgd fbeacdg aged aged
+aegbdc dbegfac gcbaf df febd egdafc deabg gdf gdfeab adfbg | bcdegaf dfeb bcegad df
+aegcdfb becdaf gdecf ag fag dcfgba badg fcbad cdgaf acefgb | abcdf cefdab ga ga
+gbcfad cefadg cegad aefdb gedacb gcfe fc cfbgead cfade caf | degac egcf geacfbd afc
+bcfad afcdbe fd ecfba cfd afde cfeabg gcbfed dacbg fdgabec | cafbged edfa fcd dabgc
+afdc adbfe bgecfad ecagdb dbcafe dfe fd agbfe bdace gdbfec | fadbe efbdgc fadbe edcba
+bdface geba ecbdag acegd afcdg ge eadbc bfecgda edg fgbdce | eg abge fadgceb abge
+fagbde fcegbd gec efcdg fdgbe ebfcag gc adcfe cgdb cagbdfe | defcg cbgdfea gcbd ecfgd
+acfbg debgf gfcdba edcbfa fbdag fgbeca cfbagde gadc da bda | dacg acbgf cedfgab caefdgb
+ca dfegca edcbgf gfcde aedbg gfdeacb dcbfea facg dgcea ace | fedcg fdagec cea ac
+acdf gcfde debcga ecbgaf cf ebgdf bagfdce cedag cef gedafc | dgcbea fc dcgeaf cdaeg
+ebagf cabgfed ed cbgad afcbge afdbge edg eagbd cedgfb aefd | fcgdbe de cgbeaf ed
+fbcdeag cafbd fgcbea fdgacb daecfb cg gca defga gbdc fdcga | abfcged agc acfgd cbfaeg
+dacfe ed ebdcag gcadfe dfbcaeg dce dfeg fbcadg bfeca acdfg | fcbdga gcbade aegdcf fbcgda
+cfdegb cbef fgdec gdfbca gdecbfa egfdca bc gbc cbegd aedgb | befc bc abegd ebcdfga
+agcefdb fdbg bf bdafe gdebaf eafdg acdbe gcebaf bef edcfga | bf fdbg efdab gefda
+gcb bdcgef dcbfg bg edbg facegb cbedf edgafbc dfgca edacbf | gb cdebfa deagfcb bg
+eafbg gfad afegbd caefbg befdgc ebagd gd bdg cfbdage acdeb | gd geafb cabed dbg
+bcedfg dc dgc aedfbcg acgbed bgfead gedbf bfdcg cedf facbg | gabfed cdebag dafegb cd
+fa adbceg afecd cafdbge eacgfb daegcf aef bcdfe fdga daceg | acedf afe fae afdg
+cdfaeg agcfb bcdgea dcafeb cef fabec ef dfgcbae defb eabcd | gdabce fdeb ebdf ecf
+cdefg ceafg gebfd cdg dc efbcdg cdgbea cfedbga cbfd fdagbe | fbcd afdgbe fabedg dcfb
+cdafgb egdb fecgabd cbfdg fcbedg feb acefg begcf be dacebf | be be ebfdca abgfcd
+eafgcd facegb acb cdbfaeg fagec dgcabe baefd cgbf cb afecb | bcafeg fcgb gfdeac eagcf
+ecgdfb deb edfgab eb faedcg agfed bfaed dbacf gbae efgdcba | fabde eb ecdgfb eabg
+aefbg bdegfa gacdb gefc fbc fc bfdcae gefbac cbfag dbgefac | ecfg fc cfge efgcdab
+gcfbed gcbae dcaef cbegad bdag bgeacf adefgcb deg adgec gd | agcbde bgad gdbfec gcfabe
+dfacb egbcda dac agdcfb fecab adecfgb bgadf cd fgeabd cgfd | gabfdec acd dc dc
+bfecg dcgeab af gadf aedbg caefdbg bgfade bafeg abf eabdcf | ebcfg gafd ebacfd fgbdace
+ge fdeab gcebfda fadcg fgead abcdef eag ebdgfa acgbef dgeb | cdagf cfdgbae fdeab eag
+dba dgfceb fbcegad bagde bcdeag bcedg bdafce agfbe ad cgad | bdcafe agdc ebdcg cdga
+edfg fedac fbegcad acgfe fabcd ead bgefac de daecgf bcaged | bafcd ade bacefg fdbac
+gdecbf edabc ef fcgead fcadg bdcfga fec ceadf dgaefbc agfe | faedgc ef gabfcd fe
+deafg eb egbaf cadegf fcdeab degb bcgaf bfe bfcdega gefdba | abgfe eb gfdaeb efdcga
+fabcd beadf efabgc fc cafdgb gcfd adfcgeb abgdce cfb dgcba | dcgf bdcgaef gdcf cfdg
+ebac acedf ceadfb cfe dbcgaf ec efcgdab degaf abfcd edgbcf | ce edgaf dgbceaf fce
+ecbag fg gacdfe edafgcb cgefa eacdfb deafc bdagcf gcf dgef | fged gedf cefdga cabge
+dgebc bcg cg gdeabf cgfeba gdfc gefbdc adbec bdefg fgcdbae | begdf cfgd eadbc gbfde
+aefdb ecgb dgaeb agdbce ega fgdacb bcadg cbdeafg ge edacfg | age fcbdaeg gea bcfegda
+cdeabg fcgda bdagc acfb dfa af cdeabfg efdgab fbcgda decgf | bcagd cfba gedfc af
+ceadb caebgfd bdfaeg cbgaf ge ega gadcbf gfce ebgcfa gebca | aecdb febgcad bgcaf fadcgbe
+daegb gfdae ceagfd bgfade feagcb fbgd bg cbagdfe ebdac ebg | gefbacd dbgf geb adgbfe
+ecadfg acdfb aefgc ecbfdag dce cfbega fcdae edga gbecdf ed | fcdba ced egfcba dega
+defgbc cgdea efag fdbcgae acbdf gcdaeb fe dfcega efc defca | fage fec dcafeg ecagfdb
+bg dbcafg gdafecb dgfcae defcg gebd cefgb bgfecd fbaec fbg | gbf dfgec bedg cfdgae
+ebgda ebd adce cdgaeb edfcgb bcagd agdcebf ed agbef gcbfda | efagb gbefa dbcfgae eadc
+ebcfdg dbe de cdabgf fgdab dgae aecbf abfgced edbaf eagdfb | bface cdafebg gadcefb fedab
+agc dabcge agbcd cabe dbagf cfgeadb gecafd gbcdfe ac gbced | cbegd beac dgbce ac
+fdagb bdeacf fga eagd gcfdb gecafb ga feabd abfgde dcbfega | bdafe abgcfe gbecfad abdgefc
+fbecd dbaef bdgc debafgc daecgf ebfcgd ebc abegfc bc gfced | fadecbg cb cdgeaf bfade
+fagbe aebfgcd gef bgadf cbagfd deafbg cfdeag ge begd beafc | bcfadeg edbgaf fcgaed ge
+gabfc gabde fbdga bfegca agfbcd df cdfagbe dcfg caefbd dbf | decfagb bdf gfcd fd
+bdafeg gf gbadf gefb cgefda daecbfg bacfed cdagb fdg fdaeb | daegcf eagdfb adgcb bagfed
+dafegb efdac bda fgedbac egfcdb bgfa fbaed bgdef debagc ba | ba bgcead bad ab
+cfged cbegdf cb ecgdb adefbcg fdcabg cdb cdagef efbc gedab | bc gdebcf gecdb bagdcf
+fbegcd gcedba eba acegf dbfa efbgd ebfadg ab fgceadb bgfea | fgbae gbedcf degfb agdebc
+ceadf fdacbe ef edgafb dfe bgaedc cadfg bcef cfebgad ecabd | cafde fabedc debac eacfd
+cd dgafe cbgfae decfg cfebg cfd gdbc febgdc fbegacd fceadb | dc beagfc aebcfg gcfeabd
+adcefbg caefgb bafd dface bdcfe cegbd fbe gdfcae dceabf fb | efb ebcgd gbdcaef fb
+fbdg gebac degbfc gd dfeagbc decfb gcd dafgce faecbd bdgec | gfdcae gfdb dg afgdce
+fb fgedca fbe gfcde gcbfde dbceaf bgeca eafbdcg dgfb fbegc | fbe cbdegf bfe gedfc
+acfbe fcbaged bgdcf cabgfd ag cagd fcbga bcfegd gfa eadbfg | afgcb gbdecf efdbcg fag
+fbegc dgca dfc fagbedc bfadcg dc ebdfca fadbg cgbfd gfdbae | dabefg egdbaf gaebdf dc
+cdbgf bdfaeg ca fgcab dgacfbe feac facgbe ebgcad bca gfbea | dafbeg cab cdagbe debfga
+gfbe ebcfag bcedaf be egfac fegdca gebca eab cbgad gfacdbe | dabcgef bcagfed gcfea bea
+bdefacg fbgedc efdagb beg geabf eg dafbce dage gfabc eabdf | gead gcafb ecfdab egfbdac
+gd gfecbd dacefb dgbf cdegf acfge agbfced becdf aedbgc gdc | gdcef cgbead gd gefacbd
+cgbfea cafed dbgefac gacb bc afbge fdabge efbac bcfgde cbe | gbac fcdbge agcb aecgdfb
+abgefc cfeba gcdba fgdcea gf fcbgaed eadfcb gbfe fga bacgf | efcba fabecd dgcbfae eagcfd
+gcdbfe fdec gcfdb bdfeg de efgba cbgdafe afgcbd cgdbea ged | cedgbf fced agfcdeb cgfbed
+dbacfge cafdb gbcfea aegc afbec ea bae bgcedf befgc edgafb | dfgeabc bfgcde faceb fbecag
+bfcgad bfegd fg dcgeb egaf bfedcag efabdc dfegba gfb abefd | gf abdgcf dcbfag fgb
+degab dgebac bfdeacg cadeb fbdeac bag debgf cgda abgecf ga | dceba fdbeg edbac dbacfge
+abdef gcbead bgce cgdab deg dgcbfa aedbg fbacdge eadcfg ge | cgfdba gcafde agfcedb fdacbge
+defabg cabdg gcfed cabe gbeacd fgadbc eb geb aedcfgb bdgce | eb dbegc dfecg dbecag
+egdabcf edcgb bcedgf cgb bgfe fcgabd bg acgfed cbaed dfegc | cgb gbc egcfad degbc
+fe agebdc gfbead fcdea abecgfd bafcde beacd cbef def cgfad | dabgfe fde adfcg bfgead
+ba fcabed bad dgacf dfgecab dcgba gdecb bdgcfa abgf caegfd | gdecb dgcfba gcdafe afbedgc
+bdgef cdbgfa acbed gedcfb efdgba cg abcgedf cgb cgdbe cfeg | edabc ebdca edbcg ecgf
+edfba bcfgead cbged defbcg ag gfadce gcaebd edabg cabg dga | fedagc bcag bdegc gaebfdc
+edab fed egcfb ecgbfad fegbd fagdcb degcaf afgebd gabdf ed | def gdefb fgedb edcagf
+fc ebfgda ebcfd cabed gcadbf baecfdg cgfe fdc egdfb gdecbf | defbg aecbfdg cadbegf adgfbe
+bgdfc fgc fdegb dgecfb fcabd egbafdc gc dgce gabefc gedbfa | fbdgce gc dbfegca cg
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--- a/2021/d09/ex1/ex1.py
+++ b/2021/d09/ex1/ex1.py
@ -0,0 +1,42 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from typing import Iterator, List, Tuple
+
+HeightMap = List[List[int]]
+Point = Tuple[int, int]
+
+
+def solve(input: List[str]) -> int:
+    height_map = [[int(c) for c in line] for line in input]
+
+    def neighbours_of(point: Point) -> Iterator[Point]:
+        for dx, dy in (-1, 0), (1, 0), (0, -1), (0, 1):
+            x, y = point[0] + dx, point[1] + dy
+            if x < 0 or x >= len(height_map):
+                continue
+            if y < 0 or y >= len(height_map[0]):
+                continue
+            yield x, y
+
+    def is_low_point(point: Point) -> bool:
+        for neighbour in neighbours_of(point):
+            if height_map[neighbour[0]][neighbour[1]] <= height_map[point[0]][point[1]]:
+                return False
+        return True
+
+    def risk_level(point: Point) -> int:
+        return 1 + height_map[point[0]][point[1]]
+
+    points = [(x, y) for x in range(len(height_map)) for y in range(len(height_map[0]))]
+    return sum(risk_level(p) for p in points if is_low_point(p))
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d09/ex1/input
+++ b/2021/d09/ex1/input
@ -0,0 +1,100 @@
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--- a/2021/d09/ex2/ex2.py
+++ b/2021/d09/ex2/ex2.py
@ -0,0 +1,61 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from typing import Iterator, List, Tuple
+
+HeightMap = List[List[int]]
+Point = Tuple[int, int]
+
+
+def solve(input: List[str]) -> int:
+    height_map = [[int(c) for c in line] for line in input]
+
+    def neighbours_of(point: Point) -> Iterator[Point]:
+        for dx, dy in (-1, 0), (1, 0), (0, -1), (0, 1):
+            x, y = point[0] + dx, point[1] + dy
+            if x < 0 or x >= len(height_map):
+                continue
+            if y < 0 or y >= len(height_map[0]):
+                continue
+            yield x, y
+
+    def is_low_point(point: Point) -> bool:
+        for neighbour in neighbours_of(point):
+            if height_map[neighbour[0]][neighbour[1]] <= height_map[point[0]][point[1]]:
+                return False
+        return True
+
+    def explore_bassin(point: Point) -> int:
+        to_be_seen = set(neighbours_of(point))
+        explored = {point}
+        bassin = {point}
+
+        while len(to_be_seen) > 0:
+            new = to_be_seen.pop()
+            explored.add(new)
+            if height_map[new[0]][new[1]] == 9:
+                continue
+            bassin.add(new)
+            for neighbour in neighbours_of(new):
+                if neighbour in explored:
+                    continue
+                to_be_seen.add(neighbour)
+
+        return len(bassin)
+
+    points = [(x, y) for x in range(len(height_map)) for y in range(len(height_map[0]))]
+    low_points = filter(is_low_point, points)
+
+    bassin_sizes = sorted(map(explore_bassin, low_points), reverse=True)
+
+    return bassin_sizes[0] * bassin_sizes[1] * bassin_sizes[2]
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d09/ex2/input
+++ b/2021/d09/ex2/input
@ -0,0 +1,100 @@
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--- a/2021/d10/ex1/ex1.py
+++ b/2021/d10/ex1/ex1.py
@ -0,0 +1,51 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from typing import List, Optional
+
+
+def solve(input: List[str]) -> int:
+    def find_illegal_char(input: str) -> Optional[int]:
+        chunks: List[str] = []
+        ends_to_start = {
+            ")": "(",
+            "]": "[",
+            "}": "{",
+            ">": "<",
+        }
+
+        for i, c in enumerate(input):
+            # Is it a chunk beginning
+            if c not in ends_to_start:
+                chunks.append(c)
+                continue
+            # Is it matching the last element on the chunk stack
+            current = chunks.pop()
+            # If not, corruption has been found
+            if ends_to_start[c] != current:
+                return i
+
+        return None
+
+    score = {
+        ")": 3,
+        "]": 57,
+        "}": 1197,
+        ">": 25137,
+    }
+
+    return sum(
+        score[line[find_illegal_char(line)]]
+        for line in input
+        if find_illegal_char(line) is not None
+    )
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d10/ex1/input
+++ b/2021/d10/ex1/input
@ -0,0 +1,110 @@
+<{[[({([{<[[([()<>]<<><>>)<[[]()]{<>()}>][<(()[])<()<>>>]]<(<(<><>)(())>)[<([]()){<><>}>{{()<>}<{}>}]>>[({
+<<({<{{{[(<{([{}{}]{{}[]}){({}())}}<<[[][]](()<>)>[{<><>}<{}<>>]>>(<[[()]([]{})]((()<>)[()()
+({<<({[<[[<[([()])]<<<{}<>><()[]>>[[()<>]<[]()>]>>([((()[])[()])]{[[()()]<<><>>][{<>[]}(()<>)]})
+(([[<<[{(({{{(()<>)[()()]}[({}<>)[[][]]]}([{{}<>}<[]()}]{[[][]][()<>]})})(([({[]{}}{[][]})
+({{<[[<<{{[{[<{}{}>{[]{}}]<([]{}){()[]}>}]<{([<><>]([]<>)){({}())({}<>)}}[[<{}<>>([]{})][[()[]]]]>}}>>]]
+[(<<<{([[[<{(<()<>>{<><>})(<[]<>>([][]))}[<[{}[]]>{<[]>(<><>)}]>([{{[]()}{[]()}}([<>[]][{}<>
+<[{[{{([<(<{{[{}<>]({}{})}{{<>[]}(()())}}(<<<>{}>(<><>)>(<<>{}>[[]<>]))>)>[{[<[[()<>]{{}<>
+{(<<[([<{<<<({()()}(<><>)}{((){})([]())}>>[<{<[]<>>{[]{}}}([()()])>]>}>]{{([{<{{[]<>}(<>)}<({}(
+((<[{(({([<{(<[][]>)[<<>{}><()<>>]}<{<{}{}>}[{()[]}<{}[]>]>>])})<[{[{([{[]()}((){})][<<>()><()()>])>]}][[({{[
+[[{([[<<[({[<<[]{}>{[][]}>(<()<>>[{}()])][([{}[]}[<><>]){[{}()]}]}[<<<{}<>>{()<>}>(<{}()>([]()))>{[[<><>][
+{{{<[([[{<[<{([]{}>{<>()}}{<(){}><()()>}>[{[[][]](<>())}[{[]<>}[<>[]]]]]{<{{{}[]}{<><>}}[[()()](<
+(([{(({[[[[{(<<>[]>((){})){<()<>><[]{}>}}{[{{}()}(()[])]((()){()<>})}]]]<[<<{(()[])<{}[]>}{
+{<<([(<([{{(<(()<>)[[][]]>{[[]{}]{(){}}})[{<(){}>[[]<>]}]}}])[[[([[{()()}{<>[]}]{[()]{[][]}}]<[((
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+[[<<([{<{((([<{}{}>(<><>)][({}[])])[[(<>{}){{}<>}](<()[]>[[]()])])[{({()}{{}{}})(({}())([]{}))}({[{}[]]{
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+({<<{[(({{<<{[[]()]{{}()}}{[<>{}]<[][]>}>{(([]())[<>[]]){<[]{}>{<><>}}}>{{{{<>[]}{{}()]}{{<>{}}[{}{}
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+[(<<{<[(<([<(<[]()><()()>)>]{({[<><>]{[][]}})}}<[([(()())[{}]]<<(){}>[<><>]>)][<<((){})>>[[{<><>}[{}()]][([]
+[<{[<[[(({{{[<{}[]><<>{}}][[{}<>]<<>()>]}{[{[]}[{}[]]]{[()[]]<{}<>>}}}[({<(){}>{{}{}}}<(()[])(
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+[(<[[[[(({[<<<<>{}><<><>>>>]<{[{{}<>}<()>]{{[]{}}[<>[]]}}<<<()[]>([]<>)><(<>{}){[]()}>>>}))[[([{<
+[([(({<{([<[({{}{}}<{}{}>)[[[]{}]({}<>)]]<[([]<>)({}[])]{(()[]){[]<>}}>>{[<{[]<>}>{[()[]]<()<>>}][<([
+{<[<[[<[{({{<[[]()][{}()]>({()[]}(()[]))}([[<>()]])})}{{<{{[<>]<[]()>}{<{}[]]}}<{{()[]}<[]<>>}([()()]<{}()>)>
+[{{(<(([([((<{{}{}}({}())>{{<>[]}<[]{}>})([{<>()}{{}<>}]{<()<>>[{}{}]})>]{{[<(<>){[]{}}>{<<>[]>[()[]]}]
+[<<(({[[({({[{[]{}}<<>[]]]{[()()]<<>()>}}{[{<>[]}<()>]}){{<<()[]>{[]{}}><<<>>[[]()]>}}})<[{{[<
+<([{{{(<{{{<<({}()){(){})>{<{}{}>{<>()}}>{(<()[]>({}()))<({}())<()()>>}}[(({[]{}}[<>{}])([{}<>])){{{{}}(<
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+[{[([{<<[([[{<<>[]>(<>())}((()())({}{}))>{[({}())<<>()>]<(<><>){()<>}>}]({([(){}]<[]<>>){<[
+[{<<[[<((({[<[[]()]>(<<>>(<>{}))]<<([]<>)[<>{}]>{<[][]>(<>())}>}(([{{}<>}{{}[]}]{[()[]]{{}{}}})<
+([<<{[([[<{<{({}())}{(()<>)}>[<[{}<>][[]()]><[<>{}]({}[])>]}<[([<>()]){[()<>]([]{})}][[[{}[]]][
+<{[[{({<{(<[[(()[])<<>[]>]<<<>()>{[]<>}>]>{[<(<>()){<>[]}>(([][]))]([<[]<>><{}{}>]([<>{}](()()
+{[([{{(([[<{<[{}<>]([]{})>[((){})<()[]>]}[[{{}<>}<[][]>]<{[]<>}([]())>]>{<{{{}<>}{(){}}]{{[]
+[{{<[([<{[[({[{}[]][(){}]}<{<>()}<[]{}>>)]<<({()<>}[[]()]){[<>[]]<()()>}>>]{[<<(<>[])<[]<>>
+<[{<[<((<({[{[{}[])(<>{})}(({}[])[<>])]})>[[([{((){})<<>>}])[<((()<>)[{}{}])[[(){}]]>{<<{}()>{
+({[[[[[[[<((<[<><>][()[]]><(<><>)>))>{{<(<<>[]>{{}})[[[]<>]({}())]><{{()<>>[[]<>]}[<{}{}>{<>{}}]>}[{<(<
+([([(<[{<[[{<{<>[]}>{{{}()]<{}()>}}<([{}()]{{}<>})[([][]){{}<>}]>]{<{{[]{}}{{}<>}}<[[]()]>>[[{()[]}{(){}}]{[
+{<{([([{<<<<{[<>()]<[]>}[[()<>]<()>]>>(([[<>[]][{}{}]])((([][]){<><>})([[]{}]<()<>})))><{<<[()()]<[]()>
+[{({[{[(([([{{{}<>}{()<>}}(([]<>){{}{}})][<{()}{{}{}}>(<<>()>[<>()])])]))<<<({((<>()){[]{}})[{
+([([(<(({<(<<<{}[]>){{<><>}[[]{}]}>[{{[][]}<<><>>}])<{<<[]>(()[])>[[{}()]<[]<>>]}{({[]()}[<><>]){{{}[]}[{
+{{[{<{((<((<<<(){}>>{([]{})[[]()]}>([({}{})]{<()>{[]{}}}))[[(<<><>>)]<<<{}{}><(){}>>[({}[])({}
+<{[({{<<((([[[(){}][{}<>]]<(<>[])<[]()>>]<[[{}()]({}())]>)({<[(){}]>{(<><>){[]{}}}})){{{<<[]()>[()<>]>[<
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+<<<{<(<[<{[[([<>()][()<>])(<<>()>[{}()])][<{<>()}>]]}<<<({<>[]}([]{}))<<(){}>>>[[({}())(())]]>{({({}[
+([<<<{<{({<[{(()<>)<()()>}]<[({}<>)]>>{[[{<>{}}(()[])](<<>>[[]<>])]}}{<<{<<>()>}><{{<>()}<<><>>}{<(){}>[(){
+{{(<<[{{({({({[]()}<{}()>)(([][])[()<>])}<{(<>())[()<>]}>)[[(([]<>)[[]<>])]]}[({[({}()){{}>]})
+<((((<{{{{{[{[(){}]([][])}[{<>{}}([]<>)]]([((){})]<[[][]][<><>]>)}}<(<{(()<>)([]{})}><([()<>]{<>()
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+<<<<[<{<[{{(<[<>]<[]{}>><(<>{}){{}()}>)[[{<>{}}{{}[]}](<[]>[<>{}])]}{{[{{}[]}(()<>)]<([]())(
+[([({[[{<{{<<{()()}<{}{}>>({{}{}}[{}{}]>>[{(<>{})<()()>}[[<>[]]<{}()>]]}[<<{<><>}(()[])>(<{}[]>
+[<<[[(({<[[([(<>[]){()[]}][(<><>)[<>[]]])]<({<{}{}>(()[])}[<{}<>>({}())])((({}{})<{}[]>)[{{}<>}{{}{}}])
+(({({[<<[<[([<<><>){[]{}}][<()<>><[]<>>])({[{}<>]<[]<>>}<({}{})[{}[]]>)][{((<><>)(()[]))}[<<{}()>{<>
+<((<[(<(<[[([{(){}}<<>()>]({(){}}{(){}}))]][{{[{[][]]{<>{}}]{[{}<>]([]{})}}}[<{[[]{}][<>()]}[(()[])<
+{((<<{({<[([(([]())([]()))(<[][]>{()})])<<[<<>[]>[<>())](<()<>><()()>)>>]>{{[{<[<>{}]<[]<>>>}<{{<><>}<
+{<<<<[((<{({<{<>[]}{<>()}><{<><>){<>()}>}([[[]()][(){}]]<<()<>>{<><>}>)){[{{<>[]}{[]()}}{(<>())
+({<<<<[{<{<{(<{}{}><()[]>)[{<>{}}]}>(<[([]{}){<><>}]{<<><>>[()[]]}}<[{()[]}{()[]}][{{}[]}{[][]}]>)}>}]
+({({{<{{{[<{{(<><>)}({[]()}{<><>})}{<[{}[]]<[]<>>>[(<>[]){()()}]}><[[<<>()><[][]>]]>]<<[{[[]()](
+<{[<([<[({([{(<>{}){()}}<([]<>)[{}{}]>)[[<()[]><{}<>>][(<>{})[()()]]]){<{({}){{}{}}}<{<>()}[[
+{((({[{<{[<({[{}()]({}{})}<(<>)(()())>)({[[]{}](<><>)}[<<>[]>[<>[]]])><<[{[]<>}][([][])<[]()>]>(
+({[((([<[(<{[(<>[])(()[])]}<[([][])([]<>)]<(()())>>>((([(){}])<(<>())<<><>>>)<[[()<>>{{}{}
+[{{((<{[(<{[{{[][]}{<><>}}[[()[]]<[][]>]]<<({}[])((){})>>}>[(<([[]()]<{}[]>)([{}<>])>({<<>[]>(<>[])}[(
+((<((<[<(<[{(<[]()>[()[]])((())(()[]))}{[[{}<>]([]{})]<[[]()]>}]>)><([<[<{[]<>}<{}[]>>[[(){}]]]({[[][]]{
+[(([([(([<<(<{<>}{[][]}>)[{[()<>]{{}{}}}({{}{}}<[]()>)]>>{([({<><>}<[]>){<{}{}>[()<>]}]<<[[]{}]{{
+[(<{<[[{[<<{<[[]<>]<[]()>>{{[]<>}}}><[[{{}()}([]<>)]][({{}<>}{{}{}})<[[][]](()())>]>><<({([]{})<<>{}>}){
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+<{{{([[([{{{<({}[])>}}<<({<>{}}{{}()))<({}{}){[]{}}>>[[(<>())[{}[]]]<<[]{}>{<>[]}>]>}([{[<<
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+[((<[{<<[<[{[{{}()}[{}[]]]<[<>[]][{}<>]>}]>]{[([([[]<>]{{}[]})[<(){}>[()[]]]]<<({}[])<[]()>>[(
+[{([<{([(({(<[[]<>]>{({}()){<><>}})([([]())[[]<>]])}(<[({}())(<>())]<{()<>}[[]<>]>>)){{([[<><>][()[]>](<[][]>
+<<(<<<{{{<<(<<[]<>>{<>()}>[<[]>])<{<{}<>>}{[{}{}]<<>[]>}>><{<<<>{}>({}<>)>}{([()[]]<<>()>)(<<><>><[]{}>)}>><
+{[<<[{{(<<[((({}{})[{}{}])(({}<>)[{}()]))]>{([[[(){}]<{}<>>][[{}[]]{()[]}]](<{[]{}}(<>[]>>))}>)}[(<
+<{{[[<[[[(((({<><>}{{}{}})<[<>()]([]())>)[<{{}<>}>{((){})[[][]]}]))<{<{[[]()]<[][]>}{<[]<>>(<>
+{<[<<([[[[{{<({}<>)<{}()>>[(<>())({}[])]}<{([][])({}<>)}>}(({[<>{}]{[]{}}}<(<>{})>)[<{[][]}{[][]}>{({}()){
+[[({{[(((({<{{<><>]}{(<><>){<><>}}>(<[()<>]<{}{}>>((<><>){<>[]}))}{<[[{}[]]([][])][{{}[]}[
+[{{<([((<<{(((<><>)<(){}>))((({}[]){<>()})(<{}()}({}{})))}><[<<{<>[]}[()<>]>{[<>{}]{[]()}}>{{
+[<{<{{({{<<<{[<><>]<[][]>}<<(){}>(<>)>>>([<{[]()}{{}[]}>{<{}()><[]<>>}]([([]())[[]]]([[]()]<<>{}>)))>
+<[{<[(<{{([[<[{}{}]><([]<>)(()())>][<((){})[[]()]>[([]<>){<><>}]]]{<{<[]<>><<>>}{<{}<>><[]{}
+{[((((((({([([(){}]([]<>)){[{}](<>[])}]{[<<>()>([]<>)]<<[][]>{[]<>}>})<<[{{}[]}(<><>)]<[()<>]
+([({(([[[([[((<>{}){{}{}}]{[()<>]((){})}]((({})(<>[])){[{}{}]<<>()>})]{({(())[<>{}]}((<>{})
+{<[<{(<[{<[{(<{}()>)[<<>[]>(()<>)]}([{()[]}<{}<>>])}(({<[]{}><{}{}>}([[]<>]{{}()})){[[{}<>]
+<<({[[<<[([(<[<><>]{<>{}}>{<(){}>(()())})<{[<>{}]<()[]>}>]<{[{<>{}}<<>()>]<{{}()}[()<>]>}<[[{}<>][{
--- a/2021/d10/ex2/ex2.py
+++ b/2021/d10/ex2/ex2.py
@ -0,0 +1,82 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from typing import Iterator, List, Optional
+
+
+def solve(input: List[str]) -> int:
+    def find_illegal_char(input: str) -> Optional[int]:
+        chunks: List[str] = []
+        ends_to_start = {
+            ")": "(",
+            "]": "[",
+            "}": "{",
+            ">": "<",
+        }
+
+        for i, c in enumerate(input):
+            # Is it a chunk beginning
+            if c not in ends_to_start:
+                chunks.append(c)
+                continue
+            # Is it matching the last element on the chunk stack
+            current = chunks.pop()
+            # If not, corruption has been found
+            if ends_to_start[c] != current:
+                return i
+
+        return None
+
+    def complete_line(input: List[str]) -> str:
+        chunks: List[str] = []
+        start_to_end = {
+            "(": ")",
+            "[": "]",
+            "{": "}",
+            "<": ">",
+        }
+
+        for c in input:
+            # Is it a chunk beginning
+            if c in start_to_end:
+                chunks.append(c)
+                continue
+            # Otherwise we must match the last open chunk
+            assert start_to_end[chunks.pop()] == c  # Sanity check
+
+        return reversed(list(start_to_end[c] for c in chunks))
+
+    def score_completion(completion: str) -> int:
+        char_score = {
+            ")": 1,
+            "]": 2,
+            "}": 3,
+            ">": 4,
+        }
+
+        score = 0
+
+        for c in completion:
+            score *= 5
+            score += char_score[c]
+
+        return score
+
+    def score_completions(completions: Iterator[str]) -> int:
+        scores = sorted(map(score_completion, completions))
+        return scores[len(scores) // 2]
+
+    incomplete_lines = filter(lambda line: find_illegal_char(line) is None, input)
+    completions = map(complete_line, incomplete_lines)
+
+    return score_completions(completions)
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d10/ex2/input
+++ b/2021/d10/ex2/input
@ -0,0 +1,110 @@
+<{[[({([{<[[([()<>]<<><>>)<[[]()]{<>()}>][<(()[])<()<>>>]]<(<(<><>)(())>)[<([]()){<><>}>{{()<>}<{}>}]>>[({
+<<({<{{{[(<{([{}{}]{{}[]}){({}())}}<<[[][]](()<>)>[{<><>}<{}<>>]>>(<[[()]([]{})]((()<>)[()()
+({<<({[<[[<[([()])]<<<{}<>><()[]>>[[()<>]<[]()>]>>([((()[])[()])]{[[()()]<<><>>][{<>[]}(()<>)]})
+(([[<<[{(({{{(()<>)[()()]}[({}<>)[[][]]]}([{{}<>}<[]()}]{[[][]][()<>]})})(([({[]{}}{[][]})
+({{<[[<<{{[{[<{}{}>{[]{}}]<([]{}){()[]}>}]<{([<><>]([]<>)){({}())({}<>)}}[[<{}<>>([]{})][[()[]]]]>}}>>]]
+[(<<<{([[[<{(<()<>>{<><>})(<[]<>>([][]))}[<[{}[]]>{<[]>(<><>)}]>([{{[]()}{[]()}}([<>[]][{}<>
+<[{[{{([<(<{{[{}<>]({}{})}{{<>[]}(()())}}(<<<>{}>(<><>)>(<<>{}>[[]<>]))>)>[{[<[[()<>]{{}<>
+{(<<[([<{<<<({()()}(<><>)}{((){})([]())}>>[<{<[]<>>{[]{}}}([()()])>]>}>]{{([{<{{[]<>}(<>)}<({}(
+((<[{(({([<{(<[][]>)[<<>{}><()<>>]}<{<{}{}>}[{()[]}<{}[]>]>>])})<[{[{([{[]()}((){})][<<>()><()()>])>]}][[({{[
+[[{([[<<[({[<<[]{}>{[][]}>(<()<>>[{}()])][([{}[]}[<><>]){[{}()]}]}[<<<{}<>>{()<>}>(<{}()>([]()))>{[[<><>][
+{{{<[([[{<[<{([]{}>{<>()}}{<(){}><()()>}>[{[[][]](<>())}[{[]<>}[<>[]]]]]{<{{{}[]}{<><>}}[[()()](<
+(([{(({[[[[{(<<>[]>((){})){<()<>><[]{}>}}{[{{}()}(()[])]((()){()<>})}]]]<[<<{(()[])<{}[]>}{
+{<<([(<([{{(<(()<>)[[][]]>{[[]{}]{(){}}})[{<(){}>[[]<>]}]}}])[[[([[{()()}{<>[]}]{[()]{[][]}}]<[((
+[{<<{<([(<[<{<{}[]>{{}[]}}(([]()))>{([(){}]<()[]>)(<[][]>{[]<>})}]>[{<<{<>()}[{}[]]>{(<><>)}>{[<[]<>>{()[]}]<
+<{{<{[[{{([({<()>{(){}}}((<>[])(<><>)))[(<[]<>>[()[]])<<()()>{<>{}}>]])<[{[{[]<>}{()()}][[{}{}]<[]>]}<{{{
+[(<[{([{({<<[<<>()>[[]()]]{<<>{}><{}<>>}><{<()()>{{}{}}}(({}<>)<()<>>)>>})({(([<{}<>>{[][]
+{(([{[<{{[({{[{}<>][()]}<{{}<>}>}(({<>[]})))]{((<[<>{}][<>[])>[[<>()]{[][]}]))<<<({}<>){{}<>}>(
+{[<{({((([[{[(<>{}){<>()}][([]{}}]}]{[<(()()){[]()}>((<>[])<(){}>)]}]){<(<<{{}<>}>>)([[{<><>}<
+{<{[(<{<[({<<[<><>]{()()}>[{()<>}<{}>]>[[<[]>][{()[]}{()}]]}(<(({}()){<><>})<(()())[<>()]>>{
+<[({[[{<([[{<{{}}>(<<><>>{[]()}}}[{{<>{}}<()<>>}{[[][]]{[]<>}}]]<((([][])<<>{}>)<((){})[{}()
+{{[{<[{<<{<<(<{}[]><(){}>)<{<>[]}[{}()]>>[{{[]<>}<()<>>}[{{}<>}(<>())]]><[(({}<>)({}<>))<<{}<>><<
+{<<({(<[(<[[{{[][]}{{}}}<[[]()]<<>())>]](<{{{}<>}{()<>}}>)>)]<(({{[[[][]]]}<[[(){}]<[]{}>]>}))>
+({{([<<{[(<<{{<>()}<[]()>}<{(){}}{{}{}}>><(<{}[]>{<>{}})<([]<>)([]())>>>)]}>>[[{<{[<<(<>{})
+<{({{({<<[{<<{<>}{{}[]}>>[[{[]<>}{()()}]<<[][]>(()())>]}]{<<{[(){}><<><>>}{{<>[]}(()<>)}>[<<(){}>[[]
+<({<([[[([({<{(){}}([][])>}<[{[][]}{<>()}]<[(){}][{}<>]>>){<({{}()}{[]{}})>{[{[]{})[()[]]]<[
+{([({[(([<{((({}()){{}<>})(<()[]>{()()})){[({}{})<<>[]>]([{}][()])}}>]{<<[<[[][]]{[][]}>({[]{}}<{}()>)
+<<{[<({[(<[({<{}{}><()()>})]{<<[<><>]>>}>){{[((<<><>><{}[]>)){<{[]()}(<>())>}]{{{({}<>){[]<>}}{{
+<<({<[{(([{({({}())(<>{})}{((){})})[<[[][]]([][])>]}<<[[<>{}][[]<>]]<([]<>)[()()]>><<<{}[]>(()())>>]])[[[
+[{<({<(({([([{[]}]<{[]()}[()<>]>]{{(()())<{}()>}{{[]()}<()<>>}}][{(<[]<>>[<>{}])[<[]<>><<><>>]}<(<<
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+{[([<<<({[{<<[<>{}]<[]<>>>>({<<>{}>((){})}<{[][]}{[]{}}>)}<{(([]{})<<>>><{{}()}(<><>)>}<{<[]
+<({[[{{{([(({[{}<>]{[]<>}}[{()<>}<(){}>])<[<{}()>[[]<>]]>)]{{[<{<>()}[{}()]><<<><>>{[][]}>]([[[][]](<>())
+[<<{{<[[{[<(<{()[]}[(){}]><[()[]]<<>{}>>)>[[[[[]{}]{[][]}]{<[]{}><(){}>}]({{<>()}<<>{}>}({()<>
+[<[[(<[[[[<<<{()<>}[[]()]>>{[[<>[]]{[]{}}]{[<>[]][[]<>]}}>]]({[({[<><>]<{}<>>}<<(){}>[{}()]>)[[<<>
+<{{({<([{({({{{}()}((){})})([([][])[[]<>]](([])[{}<>]))}<(([()<>][()[]])[<[]><{}{}>])<{({}<>)<<>()>}
+{<[[[([{[<<(({{}<>})(<{}()](<>{}))){[[<>[]]({}<>)]}><[((<>()){[][]})[({}())<{}<>>]]<({<>[]}{{}<>
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+{(<(<<{{({{<{(<>[])[[]]}{(<>{})>>{<(()())[{}{}]>{{[]{}}{{}<>}}}}(<{[{}[]]<(){}>}[[{}{}]{()<>}]>([{<>{}}[<>]]
+[{[{{[[[{([<(({}{})<[][]>)<([]{})<<>{}>>>[{[[]{}]([]<>)}{(()())[<>[]]}}]((<([]<>)[()<>]>(<{}()>)){<[<>[]](
+{<<<<{(({<<({(()())(<>{})}<([][])[[]()]>)[{{[]()}(<>)}]><{[<<>()>]{<[]()>[[]<>]}}>>}>[(<<<[{()<>}{{}<>
+[{[(<[<{<[({[{[]<>}<[][]>]{{<>()}}}[({<>[]}{{}{}}){[[]<>](<><>)}])({({{}<>}<{}<>>)}<[((){})[{
+{<[[{[(((<({([[]<>](()<>))}[{{()<>}({}())}(<[]{}>{[]{}})])<<(({})[{}{}])[(<>{})<()>]>>>))<[{{<[{{}<>}[[][]
+[[<<([{<{((([<{}{}>(<><>)][({}[])])[[(<>{}){{}<>}](<()[]>[[]()])])[{({()}{{}{}})(({}())([]{}))}({[{}[]]{
+<<((<[<(([<{[<{}<>>][<{}{}>{{}[]}]}[{<<>()>[[]{}]}{[()[]]([]{})}]><{({()()}{[]})<{[]()}[{}{}]>}{((<>(
+({<<{[(({{<<{[[]()]{{}()}}{[<>{}]<[][]>}>{(([]())[<>[]]){<[]{}>{<><>}}}>{{{{<>[]}{{}()]}{{<>{}}[{}{}
+{((<<{<<<((<(({}{})(()))[[()()]{{}<>}]>{(<()[]][{}[]])[[<>[]]<<>>]}))>([[{({()[]}{()[]})(<[][]><{}{}>)}[[[[][
+[(<<{<[(<([<(<[]()><()()>)>]{({[<><>]{[][]}})}}<[([(()())[{}]]<<(){}>[<><>]>)][<<((){})>>[[{<><>}[{}()]][([]
+[<{[<[[(({{{[<{}[]><<>{}}][[{}<>]<<>()>]}{[{[]}[{}[]]]{[()[]]<{}<>>}}}[({<(){}>{{}{}}}<(()[])(
+<{([{(<[<<<<[[{}{}]([])](<{}{}>[[][]])>{{(()[]){<>[]}}<[<><>][(){}]>}>(([[{}{}]{{}<>}](<()()>))<<(<>{})<<
+[(<[[[[(({[<<<<>{}><<><>>>>]<{[{{}<>}<()>]{{[]{}}[<>[]]}}<<<()[]>([]<>)><(<>{}){[]()}>>>}))[[([{<
+[([(({<{([<[({{}{}}<{}{}>)[[[]{}]({}<>)]]<[([]<>)({}[])]{(()[]){[]<>}}>>{[<{[]<>}>{[()[]]<()<>>}][<([
+{<[<[[<[{({{<[[]()][{}()]>({()[]}(()[]))}([[<>()]])})}{{<{{[<>]<[]()>}{<{}[]]}}<{{()[]}<[]<>>}([()()]<{}()>)>
+[{{(<(([([((<{{}{}}({}())>{{<>[]}<[]{}>})([{<>()}{{}<>}]{<()<>>[{}{}]})>]{{[<(<>){[]{}}>{<<>[]>[()[]]}]
+[<<(({[[({({[{[]{}}<<>[]]]{[()()]<<>()>}}{[{<>[]}<()>]}){{<<()[]>{[]{}}><<<>>[[]()]>}}})<[{{[<
+<([{{{(<{{{<<({}()){(){})>{<{}{}>{<>()}}>{(<()[]>({}()))<({}())<()()>>}}[(({[]{}}[<>{}])([{}<>])){{{{}}(<
+<<{[{[[<([[<(<{}<>><()[]>)<{<>()>[<>()]>>]][{{{{()<>}<{}[]>}[<[]()>[()[]]]}<{[{}](<>{})}>}[<[[<><>]<
+[{[([{<<[([[{<<>[]>(<>())}((()())({}{}))>{[({}())<<>()>]<(<><>){()<>}>}]({([(){}]<[]<>>){<[
+[{<<[[<((({[<[[]()]>(<<>>(<>{}))]<<([]<>)[<>{}]>{<[][]>(<>())}>}(([{{}<>}{{}[]}]{[()[]]{{}{}}})<
+([<<{[([[<{<{({}())}{(()<>)}>[<[{}<>][[]()]><[<>{}]({}[])>]}<[([<>()]){[()<>]([]{})}][[[{}[]]][
+<{[[{({<{(<[[(()[])<<>[]>]<<<>()>{[]<>}>]>{[<(<>()){<>[]}>(([][]))]([<[]<>><{}{}>]([<>{}](()()
+{[([{{(([[<{<[{}<>]([]{})>[((){})<()[]>]}[[{{}<>}<[][]>]<{[]<>}([]())>]>{<{{{}<>}{(){}}]{{[]
+[{{<[([<{[[({[{}[]][(){}]}<{<>()}<[]{}>>)]<<({()<>}[[]()]){[<>[]]<()()>}>>]{[<<(<>[])<[]<>>
+<[{<[<((<({[{[{}[])(<>{})}(({}[])[<>])]})>[[([{((){})<<>>}])[<((()<>)[{}{}])[[(){}]]>{<<{}()>{
+({[[[[[[[<((<[<><>][()[]]><(<><>)>))>{{<(<<>[]>{{}})[[[]<>]({}())]><{{()<>>[[]<>]}[<{}{}>{<>{}}]>}[{<(<
+([([(<[{<[[{<{<>[]}>{{{}()]<{}()>}}<([{}()]{{}<>})[([][]){{}<>}]>]{<{{[]{}}{{}<>}}<[[]()]>>[[{()[]}{(){}}]{[
+{<{([([{<<<<{[<>()]<[]>}[[()<>]<()>]>>(([[<>[]][{}{}]])((([][]){<><>})([[]{}]<()<>})))><{<<[()()]<[]()>
+[{({[{[(([([{{{}<>}{()<>}}(([]<>){{}{}})][<{()}{{}{}}>(<<>()>[<>()])])]))<<<({((<>()){[]{}})[{
+([([(<(({<(<<<{}[]>){{<><>}[[]{}]}>[{{[][]}<<><>>}])<{<<[]>(()[])>[[{}()]<[]<>>]}{({[]()}[<><>]){{{}[]}[{
+{{[{<{((<((<<<(){}>>{([]{})[[]()]}>([({}{})]{<()>{[]{}}}))[[(<<><>>)]<<<{}{}><(){}>>[({}[])({}
+<{[({{<<((([[[(){}][{}<>]]<(<>[])<[]()>>]<[[{}()]({}())]>)({<[(){}]>{(<><>){[]{}}}})){{{<<[]()>[()<>]>[<
+(<[[(<((<[[<{[[]()][()<>]}<[[][]]<[][]>>>((({}())((){}))(<{}<>]{()()}))]]>[[{<{[{}<>]}>([[{}<>](()
+<<<{<(<[<{[[([<>()][()<>])(<<>()>[{}()])][<{<>()}>]]}<<<({<>[]}([]{}))<<(){}>>>[[({}())(())]]>{({({}[
+([<<<{<{({<[{(()<>)<()()>}]<[({}<>)]>>{[[{<>{}}(()[])](<<>>[[]<>])]}}{<<{<<>()>}><{{<>()}<<><>>}{<(){}>[(){
+{{(<<[{{({({({[]()}<{}()>)(([][])[()<>])}<{(<>())[()<>]}>)[[(([]<>)[[]<>])]]}[({[({}()){{}>]})
+<((((<{{{{{[{[(){}]([][])}[{<>{}}([]<>)]]([((){})]<[[][]][<><>]>)}}<(<{(()<>)([]{})}><([()<>]{<>()
+<{<{<(<(<<<(<[[][]]<<>()>><[<>[]][[]]>)[<[<>{}][<>()]>]>{<{(()){{}()}}[<{}<>><<><>>]>[{<{}[]><<><>>}]}>{(
+{[{<<(<([({{<<[]<>>[<>{}]>{<{}<>>([]<>)}}([<<>{}>((){})}<{<>[]}>)}<<({{}()})<(<>[])[[]]>>[[<<>[]>{()[]}][[[]
+<<<<[<{<[{{(<[<>]<[]{}>><(<>{}){{}()}>)[[{<>{}}{{}[]}](<[]>[<>{}])]}{{[{{}[]}(()<>)]<([]())(
+[([({[[{<{{<<{()()}<{}{}>>({{}{}}[{}{}]>>[{(<>{})<()()>}[[<>[]]<{}()>]]}[<<{<><>}(()[])>(<{}[]>
+[<<[[(({<[[([(<>[]){()[]}][(<><>)[<>[]]])]<({<{}{}>(()[])}[<{}<>>({}())])((({}{})<{}[]>)[{{}<>}{{}{}}])
+(({({[<<[<[([<<><>){[]{}}][<()<>><[]<>>])({[{}<>]<[]<>>}<({}{})[{}[]]>)][{((<><>)(()[]))}[<<{}()>{<>
+<((<[(<(<[[([{(){}}<<>()>]({(){}}{(){}}))]][{{[{[][]]{<>{}}]{[{}<>]([]{})}}}[<{[[]{}][<>()]}[(()[])<
+{((<<{({<[([(([]())([]()))(<[][]>{()})])<<[<<>[]>[<>())](<()<>><()()>)>>]>{{[{<[<>{}]<[]<>>>}<{{<><>}<
+{<<<<[((<{({<{<>[]}{<>()}><{<><>){<>()}>}([[[]()][(){}]]<<()<>>{<><>}>)){[{{<>[]}{[]()}}{(<>())
+({<<<<[{<{<{(<{}{}><()[]>)[{<>{}}]}>(<[([]{}){<><>}]{<<><>>[()[]]}}<[{()[]}{()[]}][{{}[]}{[][]}]>)}>}]
+({({{<{{{[<{{(<><>)}({[]()}{<><>})}{<[{}[]]<[]<>>>[(<>[]){()()}]}><[[<<>()><[][]>]]>]<<[{[[]()](
+<{[<([<[({([{(<>{}){()}}<([]<>)[{}{}]>)[[<()[]><{}<>>][(<>{})[()()]]]){<{({}){{}{}}}<{<>()}[[
+{((({[{<{[<({[{}()]({}{})}<(<>)(()())>)({[[]{}](<><>)}[<<>[]>[<>[]]])><<[{[]<>}][([][])<[]()>]>(
+({[((([<[(<{[(<>[])(()[])]}<[([][])([]<>)]<(()())>>>((([(){}])<(<>())<<><>>>)<[[()<>>{{}{}
+[{{((<{[(<{[{{[][]}{<><>}}[[()[]]<[][]>]]<<({}[])((){})>>}>[(<([[]()]<{}[]>)([{}<>])>({<<>[]>(<>[])}[(
+((<((<[<(<[{(<[]()>[()[]])((())(()[]))}{[[{}<>]([]{})]<[[]()]>}]>)><([<[<{[]<>}<{}[]>>[[(){}]]]({[[][]]{
+[(([([(([<<(<{<>}{[][]}>)[{[()<>]{{}{}}}({{}{}}<[]()>)]>>{([({<><>}<[]>){<{}{}>[()<>]}]<<[[]{}]{{
+[(<{<[[{[<<{<[[]<>]<[]()>>{{[]<>}}}><[[{{}()}([]<>)]][({{}<>}{{}{}})<[[][]](()())>]>><<({([]{})<<>{}>}){
+<{[<[(<<[[[[{<{}[]><[]<>>](<{}[]>{()[]})](<[<>()][[][]]>([()()]<<>()>))]]({([<()[]>[{}()]])<{[[]()]}{<[][
+<{{{([[([{{{<({}[])>}}<<({<>{}}{{}()))<({}{}){[]{}}>>[[(<>())[{}[]]]<<[]{}>{<>[]}>]>}([{[<<
+[{<(({{<[{[[([<>{}]{<>{}})(((){})[{}[]])][{<{}<>>}[([]{})<{}>]]]}{<<([<>{}][()[]})[{{}}<{}()>]>(
+[((<[{<<[<[{[{{}()}[{}[]]]<[<>[]][{}<>]>}]>]{[([([[]<>]{{}[]})[<(){}>[()[]]]]<<({}[])<[]()>>[(
+[{([<{([(({(<[[]<>]>{({}()){<><>}})([([]())[[]<>]])}(<[({}())(<>())]<{()<>}[[]<>]>>)){{([[<><>][()[]>](<[][]>
+<<(<<<{{{<<(<<[]<>>{<>()}>[<[]>])<{<{}<>>}{[{}{}]<<>[]>}>><{<<<>{}>({}<>)>}{([()[]]<<>()>)(<<><>><[]{}>)}>><
+{[<<[{{(<<[((({}{})[{}{}])(({}<>)[{}()]))]>{([[[(){}]<{}<>>][[{}[]]{()[]}]](<{[]{}}(<>[]>>))}>)}[(<
+<{{[[<[[[(((({<><>}{{}{}})<[<>()]([]())>)[<{{}<>}>{((){})[[][]]}]))<{<{[[]()]<[][]>}{<[]<>>(<>
+{<[<<([[[[{{<({}<>)<{}()>>[(<>())({}[])]}<{([][])({}<>)}>}(({[<>{}]{[]{}}}<(<>{})>)[<{[][]}{[][]}>{({}()){
+[[({{[(((({<{{<><>]}{(<><>){<><>}}>(<[()<>]<{}{}>>((<><>){<>[]}))}{<[[{}[]]([][])][{{}[]}[
+[{{<([((<<{(((<><>)<(){}>))((({}[]){<>()})(<{}()}({}{})))}><[<<{<>[]}[()<>]>{[<>{}]{[]()}}>{{
+[<{<{{({{<<<{[<><>]<[][]>}<<(){}>(<>)>>>([<{[]()}{{}[]}>{<{}()><[]<>>}]([([]())[[]]]([[]()]<<>{}>)))>
+<[{<[(<{{([[<[{}{}]><([]<>)(()())>][<((){})[[]()]>[([]<>){<><>}]]]{<{<[]<>><<>>}{<{}<>><[]{}
+{[((((((({([([(){}]([]<>)){[{}](<>[])}]{[<<>()>([]<>)]<<[][]>{[]<>}>})<<[{{}[]}(<><>)]<[()<>]
+([({(([[[([[((<>{}){{}{}}]{[()<>]((){})}]((({})(<>[])){[{}{}]<<>()>})]{({(())[<>{}]}((<>{})
+{<[<{(<[{<[{(<{}()>)[<<>[]>(()<>)]}([{()[]}<{}<>>])}(({<[]{}><{}{}>}([[]<>]{{}()})){[[{}<>]
+<<({[[<<[([(<[<><>]{<>{}}>{<(){}>(()())})<{[<>{}]<()[]>}>]<{[{<>{}}<<>()>]<{{}()}[()<>]>}<[[{}<>][{
--- a/2021/d11/ex1/ex1.py
+++ b/2021/d11/ex1/ex1.py
@ -0,0 +1,66 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from copy import deepcopy
+from typing import Iterator, List, Set, Tuple
+
+Grid = List[List[int]]
+Point = Tuple[int, int]
+
+
+def solve(input: List[str]) -> int:
+    levels = [[int(c) for c in line] for line in input]
+
+    def step(levels: Grid) -> Tuple[Grid, int]:
+        # First step, increase levels
+        levels = [[l + 1 for l in line] for line in levels]
+
+        def excited(levels: Grid) -> Set[Point]:
+            return set(
+                (i, j)
+                for i in range(len(levels))
+                for j in range(len(levels[i]))
+                if levels[i][j] > 9
+            )
+
+        def neighbours_of(point: Point) -> Iterator[Point]:
+            for dx, dy in itertools.product((-1, 0, 1), repeat=2):
+                if dx == 0 and dy == 0:
+                    continue
+                x = point[0] + dx
+                y = point[1] + dy
+                if x < 0 or x >= len(levels):
+                    continue
+                if y < 0 or y >= len(levels[x]):
+                    continue
+                yield x, y
+
+        # Second step, do flashes
+        has_flashed: Set[Point] = set()
+        while len(flashes := (excited(levels) - has_flashed)) > 0:
+            for (i, j) in flashes:
+                has_flashed.add((i, j))
+                for x, y in neighbours_of((i, j)):
+                    levels[x][y] += 1
+
+        # Finally, bring back energy levels to 0
+        for i, j in has_flashed:
+            levels[i][j] = 0
+
+        return levels, len(has_flashed)
+
+    res = 0
+    for __ in range(100):
+        levels, flashes = step(levels)
+        res += flashes
+    return res
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d11/ex1/input
+++ b/2021/d11/ex1/input
@ -0,0 +1,10 @@
+4341347643
+5477728451
+2322733878
+5453762556
+2718123421
+4237886115
+5631617114
+2217667227
+4236581255
+4482627641
--- a/2021/d11/ex2/ex2.py
+++ b/2021/d11/ex2/ex2.py
@ -0,0 +1,67 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from copy import deepcopy
+from typing import Iterator, List, Set, Tuple
+
+Grid = List[List[int]]
+Point = Tuple[int, int]
+
+
+def solve(input: List[str]) -> int:
+    levels = [[int(c) for c in line] for line in input]
+
+    def step(levels: Grid) -> Tuple[Grid, int]:
+        # First step, increase levels
+        levels = [[l + 1 for l in line] for line in levels]
+
+        def excited(levels: Grid) -> Set[Point]:
+            return set(
+                (i, j)
+                for i in range(len(levels))
+                for j in range(len(levels[i]))
+                if levels[i][j] > 9
+            )
+
+        def neighbours_of(point: Point) -> Iterator[Point]:
+            for dx, dy in itertools.product((-1, 0, 1), repeat=2):
+                if dx == 0 and dy == 0:
+                    continue
+                x = point[0] + dx
+                y = point[1] + dy
+                if x < 0 or x >= len(levels):
+                    continue
+                if y < 0 or y >= len(levels[x]):
+                    continue
+                yield x, y
+
+        # Second step, do flashes
+        has_flashed: Set[Point] = set()
+        while len(flashes := (excited(levels) - has_flashed)) > 0:
+            for (i, j) in flashes:
+                has_flashed.add((i, j))
+                for x, y in neighbours_of((i, j)):
+                    levels[x][y] += 1
+
+        # Finally, bring back energy levels to 0
+        for i, j in has_flashed:
+            levels[i][j] = 0
+
+        return levels, len(has_flashed)
+
+    for i in itertools.count(1):
+        levels, flashes = step(levels)
+        if flashes == len(list(itertools.chain.from_iterable(levels))):
+            return i
+
+    assert False  # Sanity check
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d11/ex2/input
+++ b/2021/d11/ex2/input
@ -0,0 +1,10 @@
+4341347643
+5477728451
+2322733878
+5453762556
+2718123421
+4237886115
+5631617114
+2217667227
+4236581255
+4482627641
--- a/2021/d12/ex1/ex1.py
+++ b/2021/d12/ex1/ex1.py
@ -0,0 +1,46 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from collections import defaultdict
+from typing import Dict, List, Set
+
+Map = Dict[str, Set[str]]
+
+
+def solve(input: List[str]) -> int:
+    def parse() -> Map:
+        res: Map = defaultdict(set)
+
+        for (start, to) in map(lambda s: s.split("-"), input):
+            res[start].add(to)
+            res[to].add(start)
+
+        return res
+
+    caves = parse()
+
+    def dfs(start: str, seen: Set[str] = set()) -> int:
+        if start == "end":
+            return 1
+
+        seen = seen | {start}
+        res = 0
+
+        for dest in caves[start]:
+            if dest in seen and dest.islower():
+                continue
+            res += dfs(dest, seen)
+
+        return res
+
+    return dfs("start")
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d12/ex1/input
+++ b/2021/d12/ex1/input
@ -0,0 +1,22 @@
+ax-end
+xq-GF
+end-xq
+im-wg
+ax-ie
+start-ws
+ie-ws
+CV-start
+ng-wg
+ng-ie
+GF-ng
+ng-av
+CV-end
+ie-GF
+CV-ie
+im-xq
+start-GF
+GF-ws
+wg-LY
+CV-ws
+im-CV
+CV-wg
--- a/2021/d12/ex2/ex2.py
+++ b/2021/d12/ex2/ex2.py
@ -0,0 +1,49 @@
+#!/usr/bin/env python
+
+import itertools
+import sys
+from collections import defaultdict
+from typing import Dict, List, Set
+
+Map = Dict[str, Set[str]]
+
+
+def solve(input: List[str]) -> int:
+    def parse() -> Map:
+        res: Map = defaultdict(set)
+
+        for (start, to) in map(lambda s: s.split("-"), input):
+            res[start].add(to)
+            res[to].add(start)
+
+        return res
+
+    caves = parse()
+
+    def dfs(start: str, seen: Set[str] = set(), has_doubled_back: bool = False) -> int:
+        if start == "end":
+            return 1
+
+        seen = seen | {start}
+        res = 0
+
+        for dest in caves[start]:
+            doubles_back = False
+            if dest in seen and dest.islower():
+                if has_doubled_back or dest == "start":
+                    continue
+                doubles_back = True
+            res += dfs(dest, seen, has_doubled_back or doubles_back)
+
+        return res
+
+    return dfs("start")
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()
--- a/2021/d12/ex2/input
+++ b/2021/d12/ex2/input
@ -0,0 +1,22 @@
+ax-end
+xq-GF
+end-xq
+im-wg
+ax-ie
+start-ws
+ie-ws
+CV-start
+ng-wg
+ng-ie
+GF-ng
+ng-av
+CV-end
+ie-GF
+CV-ie
+im-xq
+start-GF
+GF-ws
+wg-LY
+CV-ws
+im-CV
+CV-wg
Author	SHA1	Message	Date
Bruno BELANYI	8e030c9d88	2021: d12: ex2: add solution	2021-12-12 15:13:41 +01:00
Bruno BELANYI	50ee5d1a50	2021: d12: ex2: add input	2021-12-12 15:13:21 +01:00
Bruno BELANYI	4e46f615cf	2021: d12: ex1: add solution	2021-12-12 15:13:10 +01:00
Bruno BELANYI	1d06b5bdb5	2021: d12: ex1: add input	2021-12-12 15:12:36 +01:00
Bruno BELANYI	56a29c6d9a	2021: d11: ex2: add solution	2021-12-11 14:12:19 +01:00
Bruno BELANYI	ead14265a5	2021: d11: ex2: add input	2021-12-11 14:12:08 +01:00
Bruno BELANYI	04565fdc99	2021: d11: ex1: add solution	2021-12-11 14:11:59 +01:00
Bruno BELANYI	086aa8db0d	2021: d11: ex1: add input	2021-12-11 14:11:35 +01:00
Bruno BELANYI	aee13702a5	2021: d10: ex2: add solution	2021-12-10 13:24:45 +01:00
Bruno BELANYI	d45a8dd667	2021: d10: ex2: add input	2021-12-10 13:24:31 +01:00
Bruno BELANYI	f69a351a0c	2021: d10: ex1: add solution	2021-12-10 13:24:20 +01:00
Bruno BELANYI	0b8976ea15	2021: d10: ex1: add input	2021-12-10 13:24:02 +01:00
Bruno BELANYI	d81856c1f7	2021: d09: ex2: add solution	2021-12-09 12:57:48 +01:00
Bruno BELANYI	4cf95d8af3	2021: d09: ex2: add input	2021-12-09 12:57:36 +01:00
Bruno BELANYI	d64484f308	2021: d09: ex1: add solution	2021-12-09 12:57:23 +01:00
Bruno BELANYI	9e004b0f2a	2021: d09: ex1: add input	2021-12-09 12:57:08 +01:00
Bruno BELANYI	17c34a3fef	2021: d08: ex2: add solution	2021-12-09 12:56:50 +01:00
Bruno BELANYI	dd388565d4	2021: d08: ex2: add input	2021-12-09 12:56:50 +01:00
Bruno BELANYI	1540559297	2021: d08: ex1: add solution	2021-12-09 12:56:50 +01:00
Bruno BELANYI	6595f4d925	2021: d08: ex1: add input	2021-12-09 12:56:50 +01:00
Bruno BELANYI	ea2b4bca26	2021: d07: ex2: add solution	2021-12-09 12:56:50 +01:00
Bruno BELANYI	2062212c8e	2021: d07: ex2: add input	2021-12-09 12:56:50 +01:00
Bruno BELANYI	b09cfca612	2021: d07: ex1: add solution	2021-12-09 12:56:50 +01:00
Bruno BELANYI	13e0e601d1	2021: d07: ex1: add input	2021-12-09 12:56:50 +01:00
Bruno BELANYI	42ba8cf8b7	2021: d06: ex2: add solution	2021-12-09 12:56:50 +01:00
Bruno BELANYI	94b7a65c5a	2021: d06: ex2: add input	2021-12-09 12:56:50 +01:00
Bruno BELANYI	7e1e268aa1	2021: d06: ex1: add solution	2021-12-09 12:56:50 +01:00
Bruno BELANYI	5de9c0eded	2021: d06: ex1: add input	2021-12-06 13:58:37 +01:00
Bruno BELANYI	1ce57b54d9	2021: d05: ex2: add solution	2021-12-06 13:58:37 +01:00
Bruno BELANYI	2440bb83c0	2021: d05: ex2: add input	2021-12-06 13:58:37 +01:00
Bruno BELANYI	01320e0157	2021: d05: ex1: add solution	2021-12-06 13:58:37 +01:00
Bruno BELANYI	4c7a2fe330	2021: d05: ex1: add input	2021-12-06 13:58:37 +01:00
Bruno BELANYI	96594f9fbf	2021: d04: ex2: add solution	2021-12-06 13:58:37 +01:00
Bruno BELANYI	cd443dc406	2021: d04: ex2: add input	2021-12-06 13:58:37 +01:00
Bruno BELANYI	e9b08f7eba	2021: d04: ex1: add solution	2021-12-06 13:58:37 +01:00
Bruno BELANYI	88cb6d3f13	2021: d04: ex1: add input	2021-12-06 13:58:37 +01:00
Bruno BELANYI	f336839b65	2021: d03: ex2: add solution	2021-12-06 13:58:37 +01:00
Bruno BELANYI	e5dd1786a6	2021: d03: ex2: add input	2021-12-06 13:58:37 +01:00
Bruno BELANYI	dbd5abfca3	2021: d03: ex1: add solution	2021-12-06 13:58:37 +01:00
Bruno BELANYI	4989f59d01	2021: d03: ex1: add input	2021-12-06 13:58:37 +01:00
Bruno BELANYI	65a285234a	2021: d02: ex2: add solution	2021-12-06 13:58:37 +01:00
Bruno BELANYI	cdeb23e6f2	2021: d02: ex2: add input	2021-12-06 13:58:37 +01:00
Bruno BELANYI	de28235f34	2021: d02: ex1: add solution	2021-12-06 13:58:37 +01:00
Bruno BELANYI	726346a2f2	2021: d02: ex1: add input	2021-12-06 13:58:37 +01:00
Bruno BELANYI	5fe99cea26	2021: d01: ex2: add solution	2021-12-06 13:58:37 +01:00
				`@ -0,0 +1 @@`
				3,1,4,2,1,1,1,1,1,1,1,4,1,4,1,2,1,1,2,1,3,4,5,1,1,4,1,3,3,1,1,1,1,3,3,1,3,3,1,5,5,1,1,3,1,1,2,1,1,1,3,1,4,3,2,1,4,3,3,1,1,1,1,5,1,4,1,1,1,4,1,4,4,1,5,1,1,4,5,1,1,2,1,1,1,4,1,2,1,1,1,1,1,1,5,1,3,1,1,4,4,1,1,5,1,2,1,1,1,1,5,1,3,1,1,1,2,2,1,4,1,3,1,4,1,2,1,1,1,1,1,3,2,5,4,4,1,3,2,1,4,1,3,1,1,1,2,1,1,5,1,2,1,1,1,2,1,4,3,1,1,1,4,1,1,1,1,1,2,2,1,1,5,1,1,3,1,2,5,5,1,4,1,1,1,1,1,2,1,1,1,1,4,5,1,1,1,1,1,1,1,1,1,3,4,4,1,1,4,1,3,4,1,5,4,2,5,1,2,1,1,1,1,1,1,4,3,2,1,1,3,2,5,2,5,5,1,3,1,2,1,1,1,1,1,1,1,1,1,3,1,1,1,3,1,4,1,4,2,1,3,4,1,1,1,2,3,1,1,1,4,1,2,5,1,2,1,5,1,1,2,1,2,1,1,1,1,4,3,4,1,5,5,4,1,1,5,2,1,3
				`@ -0,0 +1 @@`
				1101,1,29,67,1102,0,1,65,1008,65,35,66,1005,66,28,1,67,65,20,4,0,1001,65,1,65,1106,0,8,99,35,67,101,99,105,32,110,39,101,115,116,32,112,97,115,32,117,110,101,32,105,110,116,99,111,100,101,32,112,114,111,103,114,97,109,10,1133,1029,1446,1005,596,277,439,544,201,317,237,33,252,774,482,291,57,1434,153,134,385,993,677,1189,99,1082,351,80,1563,195,581,693,5,633,184,552,11,606,462,48,134,1451,850,221,336,661,276,156,932,23,98,76,327,212,489,230,819,998,1037,1561,206,159,757,207,1203,224,1459,294,39,1108,96,89,1664,353,41,83,942,771,362,193,900,676,851,277,558,368,1054,316,143,464,85,896,558,52,669,163,696,140,340,542,817,783,1436,786,81,21,669,184,430,312,1500,797,698,611,314,145,125,391,785,867,488,144,9,967,560,245,116,96,1769,314,533,25,0,1375,1307,1273,1178,332,59,26,234,487,480,615,313,629,28,707,96,637,30,350,1286,900,777,115,56,79,809,1101,13,150,741,940,20,403,384,479,622,108,325,276,609,654,535,539,62,187,414,535,140,222,845,357,55,17,8,1430,853,759,331,673,202,482,1280,714,911,409,429,604,278,478,301,408,590,329,1482,110,423,488,7,628,66,196,399,86,241,1058,501,1284,594,710,799,34,60,668,457,0,1209,20,50,1134,288,415,399,86,540,1356,285,1541,172,3,634,1387,146,669,195,403,601,758,160,970,760,43,213,68,805,50,350,292,78,252,54,1021,882,241,808,601,892,878,1401,48,191,74,1429,94,520,505,679,1133,120,485,183,362,684,520,1366,301,123,290,1248,140,44,230,572,57,1101,217,906,1012,668,85,230,32,100,472,275,78,91,19,61,732,518,189,85,1531,1255,134,489,637,792,42,36,392,603,976,651,127,486,340,534,185,890,346,906,1295,319,321,597,252,183,554,124,44,426,131,408,582,429,645,1227,574,14,1828,359,184,1830,10,288,194,949,1578,492,502,149,609,77,92,320,233,1026,123,26,188,1123,4,665,1793,331,858,481,197,424,133,933,338,7,163,1269,665,19,1,538,126,895,1751,345,895,203,175,66,305,1479,239,718,386,8,1148,203,636,1211,635,149,489,1156,1828,61,328,331,287,262,8,3,522,1427,931,1103,199,329,930,779,124,446,391,903,696,1764,16,595,522,143,296,19,872,29,546,566,256,63,1195,862,516,267,452,1287,11,547,760,77,117,988,185,293,421,118,767,70,169,456,600,755,740,1799,97,507,1165,265,1126,376,1250,408,22,674,774,361,54,558,1021,529,29,871,527,474,218,47,309,61,188,1365,725,267,235,359,1004,1771,765,8,17,103,89,967,65,302,759,1688,882,709,1469,123,548,834,355,646,404,76,257,101,627,2,66,1328,137,42,23,127,110,632,683,1163,843,1119,16,497,1756,347,958,981,57,185,204,1403,530,536,104,68,1152,95,320,959,144,281,350,622,717,112,631,150,19,938,296,1272,825,37,192,350,847,306,824,1042,320,480,857,589,137,687,93,21,1601,547,550,491,161,49,124,292,396,34,24,95,932,56,968,197,109,1300,1326,605,357,412,14,179,450,991,173,120,1402,478,77,933,88,96,49,95,596,1885,841,441,659,309,418,87,134,34,815,759,631,209,728,7,232,1304,698,140,304,1448,101,1,239,1321,362,1367,1411,279,111,633,1347,110,18,710,443,1676,64,531,386,64,518,619,893,140,301,426,1451,261,1083,115,61,943,60,891,217,475,48,436,586,31,287,196,430,357,78,161,1533,745,198,715,8,307,225,604,263,992,371,749,700,1573,573,546,480,425,47,88,66,799,388,60,736,111,81,856,29,695,141,4,271,143,939,423,3,1260,265,24,903,292,23,80,196,1245,399,123,3,532,283,366,1175,187,15,450,487,117,1041,669,59,579,159,461,598,915,666,1231,999,253,185,1016,135,1317,253,111,1261,833,26,851,120,11,63,718,682,233,76,0,50,1678,777,286,279,90,47,158,71,35,475,245,550,4,942,1816,1646,102,175,343,12,446,12,623,44,157,10,555,1173,651,361,745,1870,97,237,1628,90,233,126,1596,1146,746,383,209,55,209,318,904,144,90,21,86,4,970,262,8,210,249,871,1216,1003,172,405,821,225,2,143,915,129,598,397,583,1400,315,113,33,75,426,2,611,293,196,419,125,176,496,4,607,1425,27,48,172,972,626,227,184,1257,514,209,524,22,58,927,4,931,3,6,104,716,961,17,4,154,249,558,203,180,180,1194,935,263,535,380,1439,274,1566,873,1763,2,89,636,407,667,438,966,757,245,730,328,915,167,245,126,52,652,938,1183,320,1298,10,844,36,263,382,37,142