AOC2023D07.py

from collections import Counter

def get_puzzle_input(a_file_name: str) -> list[str]:
    with open(a_file_name) as INFILE:
        return [line.rstrip().split()[0] for line in INFILE if not line.startswith('#')]

def sort_cards(a_card: str) -> int:

    rank_map = {
        'K' : 2, 'Q' : 3, 'T' : 4,
        '9' : 5, '8' : 6, '7' : 7, '6' : 8,
        '5' : 9, '4' : 10, '3' : 11, '2' : 12,
        'J' : 13, 'A' : 14 }

    return rank_map[a_card]

def upgrade_hand(a_hand: str) -> str:

    hand_counter = Counter(a_hand)
    hand_set = set(hand_counter.keys())
    hand_set.discard('J')
    ranked_hand_set = sorted(hand_set, key=sort_cards)

    if hand_counter['J'] == 5:
        return 'KKKKK'

    if hand_counter['J'] == 4:
        for k in hand_counter:
            if k == 'J':
                pass
            else:
                return a_hand.replace('J', k)

    if hand_counter['J'] == 3:
        if len(ranked_hand_set) == 1:
            return ranked_hand_set[0] * 5
        else:
            return a_hand.replace('J', ranked_hand_set[0])

    if hand_counter['J'] == 2:
        if len(ranked_hand_set) == 1:
            return ranked_hand_set[0] * 5
        elif len(ranked_hand_set) == 2:
            for k, v in hand_counter.items():
                if k == 'J':
                    pass
                elif v == 2:
                    return a_hand.replace('J', k)
        else:
            return a_hand.replace('J', ranked_hand_set[0])

    if hand_counter['J'] == 1:
        if len(ranked_hand_set) == 4:
            return a_hand.replace('J', ranked_hand_set[0])
        elif len(ranked_hand_set) == 1:
            return ranked_hand_set[0] * 5
        elif len(ranked_hand_set) in [2, 3]:
            pairs = []
            three_of_a_kind = []

            for k, v in hand_counter.items():
                if v == 3:
                    three_of_a_kind.append(k)
                elif v == 2:
                    pairs.append(k)

            if len(three_of_a_kind) > 0:
                return a_hand.replace('J', three_of_a_kind[0])
            elif len(pairs) > 0:
                return a_hand.replace('J', sorted(pairs, key=sort_cards)[0])
            else:
                assert False, 'Why am I here?'

        else:
            assert False, 'Why am I here?'

    # No J card, return original hand

    return a_hand

hands = get_puzzle_input('AOC2023\AOC2023D07.txt')
print(f'{hands=}')

for hand in hands:
    hand_upgraded = upgrade_hand(hand)
    print(f'{hand=}, {hand_upgraded=}')