day7.py

from collections import Counter
from enum import Enum


class HandType(Enum):
    FIVE_OF_A_KIND = 7
    FOUR_OF_A_KIND = 6
    FULL_HOUSE = 5
    THREE_OF_A_KIND = 4
    TWO_PAIR = 3
    ONE_PAIR = 2
    HIGH_CARD = 1


class Hand:
    CARD_VALUES = {'T': 10, 'J': 1, 'Q': 12, 'K': 13, 'A': 14}

    def __init__(self, hand: str) -> None:
        self.hand, self.bid = hand.split()
        self.bid = int(self.bid)
        self.type: HandType = self._get_type(self.hand)

    def __repr__(self) -> str:
        return f'{self.hand}'

    @staticmethod
    def _get_type(hand: str) -> HandType:
        j_count = hand.count('J')
        counter = Counter(hand.replace('J', '') or 'J' * j_count)
        sets = len(counter)
        high = counter.most_common()[0][1] + j_count

        if sets == 1:
            return HandType.FIVE_OF_A_KIND
        elif sets == 2 and high == 4:
            return HandType.FOUR_OF_A_KIND
        elif sets == 2:
            return HandType.FULL_HOUSE
        elif sets == 3 and high == 3:
            return HandType.THREE_OF_A_KIND
        elif sets == 3 and high == 2:
            return HandType.TWO_PAIR
        elif sets == 4:
            return HandType.ONE_PAIR
        else:
            return HandType.HIGH_CARD

    @staticmethod
    def _compare_cards(left: str, right: str) -> bool:
        return (Hand.CARD_VALUES.get(left)
                or int(left)) < (Hand.CARD_VALUES.get(right) or int(right))

    def __lt__(self, other) -> bool:
        if self.type.value != other.type.value:
            return self.type.value < other.type.value

        for i in range(5):
            if self.hand[i] == other.hand[i]:
                continue
            return self._compare_cards(self.hand[i], other.hand[i])


hands = sorted(Hand(line.strip()) for line in open('input/7.txt', 'r'))
print(sum((i + 1) * hand.bid for i, hand in enumerate(hands)))