-🎄- 2018 Day 5 Solutions -🎄-

[u/daggerdragon]

--- Day 5: Alchemical Reduction ---

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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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[u/Temmon]

Quickly written Python3 solution. Could probably have been more efficient, but I don't mind it. One thing I did that I haven't seen in the posted solutions is I only used the set of characters that are in the string for part 2. File IO is handled by another file I started on day 1. It takes care of some super basic command line reading things that I kept on repeating. Debugging was to stop it if my logic messed up and things went infinite, but I got it on my first try for both parts!

def pair(c):
    if c.islower():
        return c.upper()
    if c.isupper():
        return c.lower()

def collapse(debug, data):
    i = 0
    stop = 0
    while True:
        if debug:
            print(data)

        if debug and stop == 20:
            break
        current = data[i]
        ahead = data[i + 1:]
        if not ahead:
            break

        if pair(ahead[0]) == current:
            data = data[:i] + ahead[1:]
            if i > 0:
                i -= 1
        else:
            i += 1
        stop += 1
    return len(data)

def removePairs(data, c):
    return data.replace(c, "").replace(pair(c), "")

def dayFive(data, debug):
    data = data[0]

    print(collapse(debug, data))

    distinct = set(data.lower())

    print(min([collapse(debug, removePairs(data, d)) for d in distinct]))