36 lines
997 B
Python
36 lines
997 B
Python
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# SPDX-License-Identifier: MIT
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# Copyright (c) 2020 Akumatic
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#
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#https://adventofcode.com/2020/day/15
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def readFile() -> tuple:
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with open(f"{__file__.rstrip('code.py')}input.txt", "r") as f:
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return [int(num) for num in f.readline().split(",")]
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def play(input: list, turns: int) -> int:
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mem = {val: [idx + 1] for idx, val in enumerate(input)}
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prev = input[-1]
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for turn in range(len(input) + 1, turns + 1):
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# set last spoken number
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if prev not in mem or len(mem[prev]) == 1:
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prev = 0
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else:
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prev = mem[prev][-1] - mem[prev][-2]
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# store the counter
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if prev in mem:
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mem[prev].append(turn)
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else:
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mem[prev] = [turn]
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return prev
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def part1(input: list) -> int:
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return play(input, 2020)
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def part2(input: list) -> int:
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return play(input, 30000000)
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if __name__ == "__main__":
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input = readFile()
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print(f"Part 1: {part1(input)}")
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print(f"Part 2: {part2(input)}")
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