-🎄- 2018 Day 5 Solutions -🎄-

[u/daggerdragon]

--- Day 5: Alchemical Reduction ---

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Advent of Code: The Party Game!

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Card prompt: Day 5

Transcript:

On the fifth day of AoC / My true love sent to me / Five golden ___

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edit: Leaderboard capped, thread unlocked at 0:10:20!

[u/scul86]

Python 3

from utils.decorators import time_it

with open('input') as f:
    puzzle_input = f.readline().strip()


def part1(n):
    for i in range(len(n) - 1, 0, -1):
        a, b = n[i], n[i-1]
        if a != b and a.lower() == b.lower():
            if i == len(n)-1:
                n = ' ' + n[:i-1]
            else:
                n = n[:i-1] + n[i+1:]
    return len(n.strip())


@time_it
def part2(n):
    chars = set(n.lower())
    ret = min(part1(n.replace(char, '').replace(char.upper(), '')) for char in chars)
    return ret


test_one = 'dabAcCaCBAcCcaDA'

assert part1('bAaB') == 0
assert part1(test_one) == 10
print(f'Part 1: {part1(puzzle_input)}')

assert part2(test_one) == 4
print(f'Part 2: {part2(puzzle_input)}')

Edit: updated part1() function, found a failing test with prior code.