2020/day16.py

@@ -1,5 +1,7 @@
 import sys
+from collections import defaultdict
 from functools import reduce
+from itertools import permutations
 
 
 def main():

2020/day21.py

@@ -1,43 +0,0 @@
-import re
-import sys
-from functools import reduce
-
-LINE_RE = re.compile(r"(.+) \(contains (.+)\)")
-
-def main():
-    lines = [line.rstrip() for line in sys.stdin]
-    foods = []
-    for line in lines:
-        i, a = LINE_RE.match(line).groups()
-        foods.append((set(i.split()), set(a.split(", "))))
-    ingredients = set(i for il, _ in foods for i in il)
-    allergens = set(a for _, al in foods for a in al)
-
-    # Part 1
-    matches = {}
-    while len(matches) < len(allergens):
-        for allergen in allergens:
-            p_ings = [
-                set(filter(lambda i: i not in matches, f[0]))
-                for f in foods if allergen in f[1]
-            ]
-            c_ings = reduce(lambda a, b: a & b, p_ings, ingredients)
-            if len(c_ings) == 1:
-                i = c_ings.pop()
-                matches[i] = allergen
-    clean_ings = ingredients.difference(set(matches.keys()))
-    num_appearances = sum(
-        ci in fis
-        for fis, _ in foods
-        for ci in clean_ings
-    )
-    print(f"Clean ingredients appear {num_appearances} times.")
-
-    # Part 2
-    canonical = ",".join(
-        f for f, a in sorted(matches.items(), key=lambda m: m[1])
-    )
-    print("Canonical list:", canonical)
-
-if __name__ == "__main__":
-    main()

2020/day22.py

@@ -1,57 +0,0 @@
-import sys
-
-def main():
-    lines = [line.rstrip() for line in sys.stdin]
-    deck1, deck2 = parse_lines(lines)
-
-    # Part 1
-    while deck1 and deck2:
-        c1, c2 = deck1.pop(0), deck2.pop(0)
-        if c1 > c2:
-            deck1 += [c1, c2]
-        else:
-            deck2 += [c2, c1]
-    deck_win = deck1 or deck2
-    print("Score:", score(deck_win))
-
-    # Part 2
-    deck1, deck2 = parse_lines(lines)
-    winner = rec_game(deck1, deck2)
-    deck_win = deck1 if winner == 1 else deck2
-    print("Score:", score(deck_win))
-
-def parse_lines(lines):
-    deck1, deck2 = [], []
-    for line in lines:
-        if not line:
-            continue
-        if line.startswith("P"):
-            deck = deck1 if int(line[7:8]) == 1 else deck2
-        else:
-            deck.append(int(line))
-    return deck1, deck2
-
-def score(deck):
-    return sum(c * (i + 1) for i, c in enumerate(reversed(deck)))
-
-def rec_game(deck1, deck2):
-    past_decks = set()
-    while deck1 and deck2:
-        h = tuple(deck1), tuple(deck2)
-        if h in past_decks:
-            return 1
-        past_decks.add(h)
-        c1, c2 = deck1.pop(0), deck2.pop(0)
-        if len(deck1) >= c1 and len(deck2) >= c2:
-            if rec_game(deck1[:c1], deck2[:c2]) == 1:
-                deck1 += [c1, c2]
-            else:
-                deck2 += [c2, c1]
-        elif c1 > c2:
-            deck1 += [c1, c2]
-        else:
-            deck2 += [c2, c1]
-    return 1 if deck1 else 2
-
-if __name__ == "__main__":
-    main()

2020/new.py

@@ -6,9 +6,11 @@ from datetime import date
 TEMPLATE = """\
 import sys
 
+
 def main():
     lines = [line.rstrip() for line in sys.stdin]
 
+
 if __name__ == "__main__":
     main()
 """