2024 day 13 part 1

Author: lancelote

README.md

@@ -15,7 +15,7 @@
 - 2021 - ★★★★★ ★★★★★ ★★★★★ ★★★
 - 2022 - ★★★★★ ★★★★★ ★★★★★ ★☆
 - 2023 - ★★★★★ ★★★★★ ★★★★★ ★★★☆
-- 2024 - ★★★★★ ★★★★★ ★★
+- 2024 - ★★★★★ ★★★★★ ★★☆
 
 ## How to use
 

src/year2024/day13a.py

@@ -0,0 +1,54 @@
+"""2024 - Day 13 Part 1: Claw Contraption"""
+
+import re
+import sys
+from dataclasses import dataclass
+from typing import Self
+
+type Point = tuple[int, int]
+
+
+@dataclass
+class Machine:
+    a: Point
+    b: Point
+    prize: Point
+
+    @classmethod
+    def from_text(cls, text: str) -> Self:
+        first, second, third = text.split("\n")
+
+        ac, ar = re.findall(r"\d+", first)
+        a = int(ar), int(ac)
+
+        bc, br = re.findall(r"\d+", second)
+        b = int(br), int(bc)
+
+        pc, pr = re.findall(r"\d+", third)
+        prize = int(pr), int(pc)
+
+        return cls(a, b, prize)
+
+    @property
+    def min_tokens_win(self) -> int:
+        min_cost = {(0, 0): 0}
+
+        ar, ac = self.a
+        br, bc = self.b
+
+        for ai in range(100):
+            for bi in range(1, 100):
+                nr = ar * ai + br * bi
+                nc = ac * ai + bc * bi
+
+                min_cost[(nr, nc)] = min(
+                    min_cost.get((nr - br, nc - bc), sys.maxsize) + 1,
+                    min_cost.get((nr - ar, nc - ac), sys.maxsize) + 3,
+                )
+
+        return min_cost.get(self.prize, 0)
+
+
+def solve(task: str) -> int:
+    machines = [Machine.from_text(block) for block in task.split("\n\n")]
+    return sum(x.min_tokens_win for x in machines)

tests/src/year2024/test_day13a.py

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+"""2024 - Day 13 Part 1: Claw Contraption"""
+
+from textwrap import dedent
+
+from src.year2024.day13a import solve
+
+
+def test_solve():
+    task = dedent(
+        """
+        Button A: X+94, Y+34
+        Button B: X+22, Y+67
+        Prize: X=8400, Y=5400
+
+        Button A: X+26, Y+66
+        Button B: X+67, Y+21
+        Prize: X=12748, Y=12176
+
+        Button A: X+17, Y+86
+        Button B: X+84, Y+37
+        Prize: X=7870, Y=6450
+
+        Button A: X+69, Y+23
+        Button B: X+27, Y+71
+        Prize: X=18641, Y=10279
+        """
+    ).strip()
+    assert solve(task) == 480