Add solution to 2025-12-03

Author: fuglede

2025/day03/solutions.py

@@ -0,0 +1,17 @@
+import numpy as np
+
+with open("input") as f:
+    ls = f.read().strip().split("\n")
+
+
+def greedy_largest_substr(a, to_choose):
+    res = 0
+    i = -1
+    for remaining in range(to_choose, 0, -1):
+        i += np.argmax(a[i + 1 : len(a) - remaining + 1]) + 1
+        res = res * 10 + a[i]
+    return res
+
+
+for to_choose in (2, 12):
+    print(sum(greedy_largest_substr(list(map(int, l)), to_choose) for l in ls))