aoc2020-day15-v2.py

def solve(match):
    pdict = {}
    for i, p in enumerate(data):
        pdict[int(p)] = i + 1

    turn = len(pdict) + 1
    same = 0

    while turn < match:

        if same in pdict:
            diff = turn - pdict[same]
            pdict[same] = turn
        else:
            diff = 0
            pdict[same] = turn

        same = diff
        turn += 1

    return same


data = open("day15.in").read().strip().split(',')
print(f'Part 1: {solve(2020)}')
print(f'Part 2: {solve(30000000)}')