My Advent of Code solutions in Python.
kevinyap.ca/2019/12/going-fast-in-advent-of-code/
advent-of-code
python
Add solution for 2023/07
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+63
2023/day07.py
+63
2023/day07.py
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import fileinput
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from collections import Counter
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def rank(hand, part_2=False):
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# Special-case JJJJJ; other hands Js just become the most common card.
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if part_2 and hand != 'JJJJJ':
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no_jokers = Counter(c for c in hand if c != 'J').most_common()
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hand = hand.replace('J', no_jokers[0][0])
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cmn = Counter(hand).most_common()
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# Five of a Kind
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if cmn[0][1] == 5:
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return 6
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# Four of a Kind
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elif cmn[0][1] == 4:
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return 5
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# Full House / Three of a Kind (based on second-most common card)
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elif cmn[0][1] == 3:
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return 2 + cmn[1][1]
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# Two Pair / One Pair (based on second-most common card)
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elif cmn[0][1] == 2:
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return cmn[1][1]
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return 0
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def tiebreak(hand, part_2=False):
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return tuple(card_score(c, part_2) for c in hand)
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def card_score(card, part_2=False):
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if part_2:
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return 'J23456789TQKA'.index(card)
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else:
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return '23456789TJQKA'.index(card)
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# Parse problem input.
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hands = []
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for line in fileinput.input():
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hand, bid = line.split()
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hands.append((hand, int(bid)))
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# Solve part 1.
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part_1 = 0
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for i, (hand, bid) in enumerate(sorted(hands, key=lambda h: (rank(h[0]), tiebreak(h[0]))), start=1):
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part_1 += i * bid
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print("Part 1:", part_1)
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# Solve part 2.
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part_2 = 0
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for i, (hand, bid) in enumerate(sorted(hands, key=lambda h: (rank(h[0], part_2=True), tiebreak(h[0], part_2=True))), start=1):
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part_2 += i * bid
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print("Part 2:", part_2)