day 12

1 files changed, 37 insertions, 0 deletions

diff --git a/12.py b/12.py
new file mode 100644
index 0000000..100c010
--- /dev/null
+++ b/12.py
@@ -0,0 +1,37 @@
+# pyright: strict
+import fnmatch
+from functools import cache
+from sys import stdin
+
+
+@cache
+def matching(
+    pattern: str, groups: tuple[int, ...], length: int, min_offset: int = 0
+) -> int:
+    if not groups:
+        return 1 if "#" not in pattern else 0
+    total = 0
+    for offset in range(min_offset, length - sum(groups) - len(groups) + 2):
+        base = "." * offset + "#" * groups[0]
+        if not fnmatch.fnmatch(base, pattern[: len(base)]):
+            continue
+        total += matching(
+            pattern[len(base) :], groups[1:], length - len(base), min_offset=1
+        )
+    return total
+
+
+inp: list[tuple[str, tuple[int, ...]]] = []
+for line in stdin:
+    pattern, rest = line.rstrip().split(maxsplit=1)
+    groups = tuple(map(int, rest.split(",")))
+    inp.append((pattern, groups))
+
+
+print(sum(matching(pattern, groups, len(pattern)) for pattern, groups in inp))
+
+p2 = 0
+for pattern, groups in inp:
+    pattern = "?".join([pattern] * 5)
+    p2 += matching(pattern, groups * 5, len(pattern))
+print(p2)