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36 lines
1.1 KiB
Python
36 lines
1.1 KiB
Python
import math
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d = [ x.split(',') for x in open('input').read().splitlines() ]
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def a(d): #To be honest, I could've done this way quicker manually and got on the leaderboard. Formula is x - ID mod x for the waiting time
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x = int(d[0][0])
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ids = [ int(x) for x in d[1] if x != 'x' ]
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delta = { id:(id - (x % id)) for id in ids if ( x := int(d[0][0]) )}
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minId = min(delta, key=delta.get)
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return (delta[minId]*minId)
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print(a(d))
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def b(d):
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d = [ ',(t+'+str(y)+')mod'+str(d[y])+'=0' for y in {i:d[i] for i in range(len(d))} if d[y] != 'x']
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return ''.join(d)[1:]
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# I'm a math noob, so I just saw what everyone else is talking about and found this chinese remainder theorem.
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# Why does this work? I DONT KNOW.
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# I'll probably learn this when I get some formal CS education, so for now I'm just giving myself a rest for this part.
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# Used a solver for that.
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# x = 760171380521445
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# x ≡ 0 mod 17 => x = n*17+0
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# x ≡ −7 mod 41 => x = n*41-7 ??? # -7 because of
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# x ≡ −17 mod 643
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# x ≡ −25 mod 23
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# x ≡ −30 mod 13
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# x ≡ −46 mod 29
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# x ≡ −48 mod 433
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# x ≡ −54 mod 37
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# x ≡ −67 mod 19
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print(b(d[1]))
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