2015: d16: ex2: add solution

2015/d16/ex2/ex2.py

@@ -0,0 +1,69 @@
+#!/usr/bin/env python
+
+import sys
+from typing import NamedTuple
+
+
+class Sue(NamedTuple):
+    children: int | None = None
+    cats: int | None = None
+    samoyeds: int | None = None
+    pomeranians: int | None = None
+    akitas: int | None = None
+    vizslas: int | None = None
+    goldfish: int | None = None
+    trees: int | None = None
+    cars: int | None = None
+    perfumes: int | None = None
+
+    def matches(self, reading: dict[str, int | None]) -> bool:
+        for name, expected in reading.items():
+            assert expected is not None  # Sanity check
+            val = getattr(self, name)
+            if name in ("cats", "trees"):
+                if val is not None and val <= expected:
+                    return False
+            elif name in ("pomeranians", "goldfish"):
+                if val is not None and val >= expected:
+                    return False
+            else:
+                if val is not None and val != expected:
+                    return False
+        return True
+
+
+def solve(input: str) -> int:
+    def parse_line(input: str) -> Sue:
+        _, other = input.split(": ", 1)
+        raw_items = other.split(", ")
+        items = {
+            name: int(val) for name, val in (item.split(": ") for item in raw_items)
+        }
+        return Sue(**items)
+
+    def parse(input: str) -> list[Sue]:
+        return [parse_line(line) for line in input.splitlines()]
+
+    aunts = parse(input)
+    reading = Sue(
+        children=3,
+        cats=7,
+        samoyeds=2,
+        pomeranians=3,
+        akitas=0,
+        vizslas=0,
+        goldfish=5,
+        trees=3,
+        cars=2,
+        perfumes=1,
+    )
+    return next(i for i, sue in enumerate(aunts, 1) if sue.matches(reading._asdict()))
+
+
+def main() -> None:
+    input = sys.stdin.read()
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()