2022: d02: ex1: add solution

2022/d02/ex1/ex1.py

@@ -0,0 +1,61 @@
+#!/usr/bin/env python
+
+import enum
+import sys
+
+
+class Outcome(enum.IntEnum):
+    Lose = 0
+    Draw = 3
+    Win = 6
+
+
+class Choice(enum.IntEnum):
+    Rock = 1
+    Paper = 2
+    Scissors = 3
+
+    @classmethod
+    def from_input(cls, input: str) -> "Choice":
+        match input:
+            case "A" | "X":
+                return cls.Rock
+            case "B" | "Y":
+                return cls.Paper
+            case "C" | "Z":
+                return cls.Scissors
+        assert False  # Sanity check
+
+
+def score(other: Choice, you: Choice) -> int:
+    def outcome() -> Outcome:
+        if other == you:
+            return Outcome.Draw
+        if other == other.Rock and you == other.Paper:
+            return Outcome.Win
+        if other == other.Paper and you == other.Scissors:
+            return Outcome.Win
+        if other == other.Scissors and you == other.Rock:
+            return Outcome.Win
+        return Outcome.Lose
+
+    return you + outcome()
+
+
+Round = tuple[Choice, Choice]
+
+
+def solve(input: list[Round]) -> int:
+    return sum(map(lambda round: score(*round), input))
+
+
+def main() -> None:
+    input: list[Round] = [
+        (Choice.from_input(round[0]), Choice.from_input(round[2]))
+        for round in sys.stdin.readlines()
+    ]
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()