Day 04

day04/part2.py

@@ -0,0 +1,16 @@
+#!/usr/bin/env python3
+from collections import defaultdict
+
+lines = (x.strip() for x in open("input.txt"))
+result = 0
+tickets = defaultdict(int, {i: 1 for i in range(0)})
+
+for idx, line in enumerate(lines):
+    tickets[idx] += 1
+    winnings = set(int(x.strip()) for x in line[line.find(":")+1:line.find("|")].split(" ") if len(x))
+    you_have = set(int(x.strip()) for x in line[line.find("|")+1:].split(" ") if len(x))
+    num_overlap = len(you_have.intersection(winnings))
+    for i in range(idx+1, idx+1+num_overlap):
+        tickets[i] += tickets[idx]
+
+print(sum(tickets.values()))