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#!/usr/bin/env python3
import aoc20
import sys
def pt1(_in):
nums = [int(n) for n in _in[0].split(",")]
prev = {n: i for i, n in enumerate(nums)}
while len(nums) < 2020:
cur = nums[-1]
if cur not in prev:
nums.append(0)
prev[cur] = len(nums) - 2
else:
nums.append(len(nums) - 1 - prev[cur])
prev[cur] = len(nums) - 2
return nums[2019]
def pt2(_in):
nums = [int(n) for n in _in[0].split(",")]
amount = 3
cur = nums[-1]
prev = {n: i for i, n in enumerate(nums)}
while amount < 30000000:
if amount % 300000 == 0:
print(amount // 300000)
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
if __name__ == "__main__":
input = aoc20.read_input(sys.argv[1:], 15)
print(pt1(input))
print(pt2(input))
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