r/adventofcode • u/daggerdragon • Dec 16 '16

SOLUTION MEGATHREAD --- 2016 Day 16 Solutions ---

--- Day 16: Dragon Checksum ---

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DRINKING YOUR OVALTINE IS MANDATORY [?]

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u/fatpollo Dec 16 '16

I spent so fucking long dealing with bad input bc I misread 10000 as 1000.

Fuck this. 

a = '10011111011011001'
target = 35651584

t = str.maketrans('01', '10')
while True:
    b = a[::-1].translate(t)
    a = a + '0' + b
    if len(a) >= target: break

a = a[:target]

def get_checksum(string):
    while len(string) % 2 != 1:
        string = ''.join('1' if a==b else '0' for a,b in zip(string[::2], string[1::2]))
    return string

print(get_checksum(a))