Add solution to 2025-12-10

Author: fuglede

2025/day10/solutions.py

@@ -0,0 +1,64 @@
+import numpy as np
+from scipy.optimize import linprog
+from collections import deque
+
+
+with open("input") as f:
+    ls = f.read().strip().split("\n")
+
+
+def solve1(l):
+    goal, *buttons, _ = l.split(" ")
+    goal = set(i for i, x in enumerate(goal[1:-1]) if x == "#")
+
+    moves = []
+    for b in buttons:
+        b = b[1:-1]
+        b = {int(x) for x in b.split(",")}
+        moves.append(b)
+
+    # BFS
+    q = deque()
+    q.append((set(), 0))
+    seen = set()
+    while q:
+        curr, steps = q.popleft()
+        if curr == goal:
+            return steps
+        for m in moves:
+            newset = curr ^ m
+            if newset in seen:
+                continue
+            seen.add(frozenset(newset))
+            q.append((newset, steps + 1))
+
+
+print(sum(solve1(l) for l in ls))
+
+
+# Part 2
+def solve2(l):
+    _, *buttons, counters = l.split(" ")
+    goal = tuple(map(int, counters[1:-1].split(",")))
+    moves = []
+    for b in buttons:
+        b = b[1:-1]
+        b = {int(x) for x in b.split(",")}
+        moves.append(b)
+
+    c = [1 for _ in moves]
+    A_eq = []
+    b_eq = []
+    for i in range(len(goal)):
+        A_eq.append([1 if i in move else 0 for move in moves])
+        b_eq.append(goal[i])
+    A_eq = np.array(A_eq)
+    b_eq = np.array(b_eq)
+    res = linprog(
+        c, A_eq=A_eq, b_eq=b_eq, bounds=(0, None), method="highs", integrality=True
+    )
+    # print(res)
+    return res.fun
+
+
+print(sum(solve2(l) for l in ls))