43 lines
838 B
Ruby
43 lines
838 B
Ruby
require "set"
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input = STDIN.read.chomp
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commands = input.split ", "
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position = [0, 0] # Cartesian coordinates, +x is right, +y is up
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direction = 0 # North I guess
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visited_positions = Set.new([position.clone])
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first_revisited_position = nil
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commands.each do |command|
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turn = command[0] == "L" ? 1 : -1
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distance = command[1..].to_i
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direction += turn
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direction = direction % 4
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distance.times do
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case direction
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when 0
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position[1] += 1
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when 1
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position[0] += 1
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when 2
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position[1] -= 1
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when 3
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position[0] -= 1
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end
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if !visited_positions.add?(position.clone)
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if first_revisited_position.nil?
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first_revisited_position = position.clone
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end
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end
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end
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end
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part_1 = position.map(&:abs).sum
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part_2 = first_revisited_position.map(&:abs).sum
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puts "Part 1: #{part_1}"
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puts "Part 2: #{part_2}"
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