66 lines
1.6 KiB
Crystal
66 lines
1.6 KiB
Crystal
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require "advent"
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def parse_range(str)
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data = str.match(/([a-z ]+): (\d+)-(\d+) or (\d+)-(\d+)/).not_nil!
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return {data[1], (data[2].to_i32..data[3].to_i32), (data[4].to_i32.. data[5].to_i32)}
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end
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fields, your, nearby = input(2020, 16).split("\n\n")
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fields = fields.lines.map { |l| parse_range(l) }
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your = your.lines[1].split(",").map(&.to_i32)
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nearby = nearby.lines[1..].map(&.split(",").map(&.to_i32))
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def part1(input)
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fields, your, nearby = input
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all_ranges = [] of Range(Int32, Int32)
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fields.each do |a|
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all_ranges << a[1] << a[2]
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end
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nearby.select! do |nb|
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nb.all? do |n|
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all_ranges.any? &.includes?(n)
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end
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end
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nearby << your
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field_map = {} of String => Set(Int32)
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fields.each do |f|
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field_map[f[0]] = Set(Int32).new
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nearby[0].size.times do |i|
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next if field_map.values.includes? i
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all_match = nearby.all? do |nb|
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f[1].includes?(nb[i]) || f[2].includes?(nb[i])
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end
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if all_match
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field_map[f[0]] << i
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end
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end
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end
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sum = 1_u64
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numbers = (0...nearby[0].size).to_a
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solved = {} of String => Int32
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while solved.size != fields.size
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cleared = [] of {String, Int32}
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field_map.each do |k, v|
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next unless v.size == 1
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cleared << {k, v.to_a[0]}
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end
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cleared.each do |f,n|
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solved[f] = n
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field_map.each do |k, v|
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v.delete n
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end
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end
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end
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fields.each do |f|
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next unless f[0].starts_with? "departure"
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sum *= your[solved[f[0]]]
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end
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sum
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end
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def part2(input)
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end
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puts part1({fields, your, nearby})
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puts part2({fields, your, nearby})
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