Do day 3 and 4 for 2025

2025/d03.py

@@ -0,0 +1,35 @@
+from lib import get_data
+
+data = get_data(__file__)
+
+
+def max_joltage(xs: str, target_len: int) -> int:
+    def dynamic(xs: str) -> dict[int, str]:
+        if len(xs) == 0:
+            return {0: ""}
+
+        rs = dynamic(xs[1:])
+        for i in range(target_len, 0, -1):
+            if not (i - 1) in rs:
+                continue
+            nv = int(xs[0] + rs[i - 1])
+            if not i in rs:
+                rs[i] = str(nv)
+            elif nv > int(rs[i]):
+                rs[i] = str(nv)
+        return rs
+
+    rs = dynamic(xs)
+    return int(rs[target_len])
+
+
+r1 = 0
+r2 = 0
+for line in data.splitlines():
+    r1 += max_joltage(line, 2)
+    r2 += max_joltage(line, 12)
+
+
+print(r1)
+print(r2)
+