29 lines
413 B
Crystal
29 lines
413 B
Crystal
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require "advent"
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INPUT = input(2020, 25).lines.map(&.to_i64)
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def transform(s)
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i = 1_i64
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c = 0
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loop do
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c += 1
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i = (i * s) % 20201227
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yield i, c
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end
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end
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def find_size(s, goal)
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transform(s) do |n, c|
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return c if n == goal
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end
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end
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def part1(input)
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goal = find_size(7, input[0])
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puts goal
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transform(input[1]) do |n, c|
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return n if c == goal
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end
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end
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puts part1(INPUT.clone)
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