2025: d12: ex1: add solution

2025/d12/ex1/ex1.py

@@ -0,0 +1,56 @@
+#!/usr/bin/env python
+
+import sys
+from typing import NamedTuple
+
+
+class Point(NamedTuple):
+    x: int
+    y: int
+
+
+class Region(NamedTuple):
+    size: Point
+    pieces: list[int]
+
+    @classmethod
+    def from_str(cls, input: str) -> "Region":
+        raw_size, *raw_pieces = input.split(" ")
+        size = Point(*map(int, raw_size.removesuffix(":").split("x")))
+        pieces = [int(n) for n in raw_pieces]
+        return cls(size, pieces)
+
+
+def solve(input: str) -> int:
+    def parse_shape(input: list[str]) -> set[Point]:
+        return {
+            Point(x, y)
+            for x, line in enumerate(input)
+            for y, c in enumerate(line)
+            if c == "#"
+        }
+
+    def parse(input: str) -> tuple[list[set[Point]], list[Region]]:
+        *raw_shapes, raw_regions = input.split("\n\n")
+        shapes = [parse_shape(shape.splitlines()[1:]) for shape in raw_shapes]
+        regions = [Region.from_str(region) for region in raw_regions.splitlines()]
+        return shapes, regions
+
+    def can_fit_stupid(shapes: list[set[Point]], region: Region) -> bool:
+        # Does not actually try to fit the pieces, just checks the area
+        # This does *not* work on the sample input
+        minimum_size = sum(len(shapes[i]) * n for i, n in enumerate(region.pieces))
+        region_size = region.size.x * region.size.y
+        return minimum_size <= region_size
+
+    shapes, regions = parse(input)
+    return sum(can_fit_stupid(shapes, region) for region in regions)
+
+
+def main() -> None:
+    input = sys.stdin.read()
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()