2018: d14: ex2: add solution

2018/d14/ex2/ex2.py

@@ -0,0 +1,27 @@
+#!/usr/bin/env python
+
+import sys
+
+
+def solve(input: str) -> int:
+    digits = [int(n) for n in input.strip()]
+
+    scores = [3, 7]
+    elves = [0, 1]
+
+    while scores[-len(digits) :] != digits and scores[-len(digits) - 1 : -1] != digits:
+        sum = scores[elves[0]] + scores[elves[1]]
+        scores.extend(map(int, str(sum)))
+        elves = [(elf + 1 + scores[elf]) % len(scores) for elf in elves]
+
+    left_of_digits = len(scores) - len(digits) - (scores[-len(digits) :] != digits)
+    return left_of_digits
+
+
+def main() -> None:
+    input = sys.stdin.read()
+    print(solve(input))
+
+
+if __name__ == "__main__":
+    main()