35 lines
662 B
Crystal
35 lines
662 B
Crystal
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require "advent"
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INPU = input(2020, 13).lines
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INPUT = {INPU[0].to_i32, INPU[1].split(",")}
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def part1(input)
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early, busses = input
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busses.reject! &.==("x")
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busses = busses.map &.to_i32
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bbus = busses.min_by do |b|
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(early / b).ceil * b
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end
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diff = bbus * (((early/bbus).ceil * bbus).to_i32 - early)
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end
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def part2(input)
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_, busses = input
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busses = busses.map_with_index do |x, i|
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x.to_i32?.try { |n| { n, i } }
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end
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busses = busses.compact
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n = 0_i64
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iter = 1_i64
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busses.each do |m, i|
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while (n + i) % m != 0
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n += iter
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end
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iter *= m
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end
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puts n
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puts busses
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end
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puts part1(INPUT.clone)
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puts part2(INPUT.clone)
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