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#!/usr/bin/env python3
import aoc20
import sys
def say_nth(start, nth):
amount = len(start)
cur = start[-1]
prev = {n: i for i, n in enumerate(start)}
while amount < nth:
if cur not in prev:
new = 0
prev[cur] = amount - 1
else:
new = amount - 1 - prev[cur]
prev[cur] = amount - 1
cur = new
amount += 1
return cur
def pt1(_in):
return say_nth([int(n) for n in _in[0].split(",")], 2020)
def pt2(_in):
return say_nth([int(n) for n in _in[0].split(",")], 30000000)
if __name__ == "__main__":
input = aoc20.read_input(sys.argv[1:], 15)
print(pt1(input))
print(pt2(input))
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