def parse(s)
  s.split(",").map { |ss| { ss[0], ss[1..].to_i32 } }
end

def run_line(l)
  poses = Set({Int32,Int32}).new
  step_map = {} of {Int32,Int32} => Int32
  x, y, steps = 0, 0, 0
  l.each do |cmd|
    dir, len = cmd
    dx, dy = 0, 0
    case dir
    when 'U'
      dy = 1
    when 'D'
      dy = -1
    when 'L'
      dx = -1
    when 'R'
      dx = 1
    end
    len.times do |i|
      x += dx
      y += dy
      steps += 1
      poses << {x,y}
      step_map[{x,y}] ||= steps
    end
  end
  return {poses, step_map}
end

lines = File.read("day3.txt").lines.map(&.chomp)
# wire1 = parse("R8,U5,L5,D3")
# wire2 = parse("U7,R6,D4,L4")
# puts run_line(wire1)
# puts run_line(wire2)
wire1 = parse(lines[0])
wire2 = parse(lines[1])
poses1, steps1 = run_line(wire1)
poses2, steps2 = run_line(wire2)
puts (poses1 & poses2).min_of { |p| p[0] + p[1] }
puts (poses1 & poses2).min_of { |p| steps1[p] + steps2[p] }