2020: d03: ex2: add solution

2020/d03/ex2/ex2.py

@@ -0,0 +1,33 @@
+#!/usr/bin/env python
+
+import sys
+from math import prod
+from typing import List, Tuple
+
+
+def solve(trees: List[str], delta: Tuple[int, int]) -> int:
+    x, y = 0, 0
+    sum = 0
+    while True:
+        x += delta[0]
+        y += delta[1]
+        if y >= len(trees):
+            break
+        sum += trees[y][x % len(trees[0])] == "#"
+    return sum
+
+
+def main() -> None:
+    input = [line.strip() for line in sys.stdin.readlines()]
+    deltas = [
+        (1, 1),
+        (3, 1),
+        (5, 1),
+        (7, 1),
+        (1, 2),
+    ]
+    print(prod(solve(input, delt) for delt in deltas))
+
+
+if __name__ == "__main__":
+    main()