48 lines
1.1 KiB
Python
48 lines
1.1 KiB
Python
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def read_file():
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with open("input.txt","r") as f:
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return [int(x) for x in f.read().split(',')]
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def numbers_spoken(seed, limit):
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"""Stores all numbers spoken."""
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numbers = seed
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i = len(seed)
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number = seed[-1]
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while len(numbers) != limit:
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past = numbers[:-1]
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if number not in past:
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numbers.append(0)
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number = 0
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else:
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last_spoken = len(past) + 1
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most_recently_spoken = (len(past) - past[::-1].index(number))
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turns_ago = last_spoken - most_recently_spoken
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numbers.append(turns_ago)
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number = turns_ago
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return numbers[-1]
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def part1(seed):
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return numbers_spoken(seed,2020)
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def number_spoken_on_turn(seed, turn):
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"""Only cares about specific turn."""
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last_spoken = {last: i+1 for i, last in enumerate(seed)}
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number = seed[-1]
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for i in range(len(seed),turn):
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if number not in last_spoken:
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last_spoken[number] = i
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number = 0
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else:
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last = last_spoken[number]
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last_spoken[number] = i
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number = last_spoken[number] - last
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return(number)
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def part2(seed):
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return number_spoken_on_turn(seed,30000000)
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def main():
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seed = read_file()
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print(part1(seed), part2(seed))
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if __name__ == "__main__":
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main()
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