add day4

day4/day4.py

@@ -0,0 +1,77 @@
+import sys
+sys.path.append('../lib')
+
+import tools, re
+
+class Card(object):
+    card_re = re.compile(r'Card +(\d+): ')
+    def __init__(self, inp):
+        m = self.card_re.search(inp)
+        if not m:
+            print(inp)
+        self.card_num = m.group(1)
+        inp = inp.replace(m.group(0), '')
+        winning, have = inp.split('|')
+        self.winning = [int(x) for x in winning.split()]
+        self.have = [int(x) for x in have.split()]
+
+    def __str__(self):
+        s = 'card number: ' + self.card_num + '\n'
+        s += 'winning: ' + ' '.join(str(x) for x in self.winning) + '\n'
+        s += 'have: ' + ' '.join(str(x) for x in self.have) + '\n'
+        return s
+
+    def _count_winning_in_have(self):
+        count = 0
+        for x in self.winning:
+            if x in self.have:
+                count += 1
+        return count
+
+    def count_card_worth_points(self):
+        n = self._count_winning_in_have()
+        if n == 0:
+            return 0
+        worth = 1
+        for _ in range(n-1):
+            worth *= 2
+        return worth
+            
+
+class CardSet(object):
+    def __init__(self, inp):
+        self.cards = []
+        self.cards.extend([Card(l) for l in inp])
+
+    def __str__(self):
+        out = [str(card) for card in self.cards]
+        return ''.join(out)
+
+    def count_cards_worth(self) -> int:
+        w = [c.count_card_worth_points() for c in self.cards]
+        return sum(w)
+
+    def count_total_copies(self):
+        copies = [0 for _ in range(len(self.cards))]
+        for i in range(len(self.cards)):
+            copies[i] += 1
+            for _ in range(copies[i]):
+                matching = self.cards[i]._count_winning_in_have()
+                if i + matching > len(self.cards):
+                    matching = len(self.cards) - 1 - i
+                for j in range(1, matching+1):
+                    copies[i+j] += 1
+        return sum(copies)
+
+if __name__ == '__main__':
+    r = tools.Reader('input.txt')
+    lines = r.read()
+
+    cs = CardSet(lines)
+    x = cs.count_cards_worth()
+    print(x)
+
+    y = cs.count_total_copies()
+    print(y)
+
+