Python: Solved day 1 and 2

02/py/solution.py

@@ -0,0 +1,82 @@
+from pathlib import Path
+
+
+WINS_OVER = {
+    "A": "C",
+    "B": "A",
+    "C": "B",
+    "X": "C",
+    "Y": "A",
+    "Z": "B",
+}
+
+
+BASE_SCORE = {
+    "A": 1,
+    "B": 2,
+    "C": 3,
+    "X": 1,
+    "Y": 2,
+    "Z": 3,
+}
+
+
+def score(a: str, b: str) -> int:
+    result = BASE_SCORE.get(b)
+
+    if BASE_SCORE[a] == BASE_SCORE[b]:
+        # Draw
+        result += 3
+    elif a == WINS_OVER[b]:
+        # Win
+        result += 6
+
+    return result
+
+
+def winning_shape(other: str, goal: str) -> str:
+    if goal == "Y":
+        # Draw
+        return other
+
+    if goal == "X":
+        # Win
+        return WINS_OVER[other]
+
+    if goal == "Z":
+        # Lose
+        return next(k for k, v in WINS_OVER.items() if v == other)
+
+
+# Setup
+
+# Example data
+# data = """
+# A Y
+# B X
+# C Z
+# """
+
+data = (Path(__file__).parents[1] / "input").read_text()
+
+# Problem solving - part 1
+scores = [
+    score(*parts) for line in data.splitlines() if (parts := line.split(maxsplit=1))
+]
+
+total = sum(scores)
+print(total)
+
+# Problem solving - part 2
+assert winning_shape("B", "Z") == "C"  # Win against paper -> scissors
+assert winning_shape("B", "Y") == "B"  # Draw against paper -> paper
+assert winning_shape("B", "X") == "A"  # Lose against paper -> rock
+
+scores = [
+    score(parts[0], winning_shape(parts[0], parts[1]))
+    for line in data.splitlines()
+    if (parts := line.split(maxsplit=1))
+]
+
+total = sum(scores)
+print(total)