Advent of Code December 1

day1.rb

#!/bin/ruby

# moves = ["R5", "L5", "R5", "R3"] # ok
# moves = ["R2", "R2", "R2"] # ok
# moves = ["R2", "L3"] # ok

moves = ["L2", "L5", "L5", "R5", "L2", "L4", "R1", "R1", "L4", "R2", "R1", "L1", "L4", "R1", "L4", "L4", "R5", "R3", "R1", "L1", "R1", "L5", "L1", "R5", "L4", "R2", "L5", "L3", "L3", "R3", "L3", "R4", "R4", "L2", "L5", "R1", "R2", "L2", "L1", "R3", "R4", "L193", "R3", "L5", "R45", "L1", "R4", "R79", "L5", "L5", "R5", "R1", "L4", "R3", "R3", "L4", "R1""85", "L5", "L3", "L1", "R5", "L2", "R1", "R3", "R2", "L3", "L4", "L2", "R2", "L3", "L2", "L2", "L3", "L5", "R3", "R4", "L5", "R1", "R2", "L2", "R4", "R3", "L4", "L3", "L1", "R3", "R2", "R1", "R1", "L3", "R4", "L5", "R2", "R1", "R3", "L3", "L2", "L2", "R2", "R1", "R2", "R3", "L3", "L3", "R4", "L4", "R4", "R4", "R4", "L3", "L1", "L2", "R5", "R2", "R2", "R2", "L4", "L3", "L4", "R4", "L5", "L4", "R2", "L4", "L4", "R4", "R1", "R5", "L2", "L4", "L5", "L3", "L2", "L4", "L4", "R3", "L3", "L4", "R1", "L2", "R3", "L2", "R1", "R2", "R5", "L4", "L2", "L1", "L3", "R2", "R3", "L2", "L1", "L5", "L2", "L1", "R4"]

class BunnyHQWalker
  def initialize
    @current_direction = :north
    @stack = {
      :north => 0,
      :south => 0,
      :east => 0,
      :west => 0
    }
  end

  def turn(direction, move)
    case @current_direction
    when :north
      @current_direction = (direction == :left) ? :west : :east
    when :south
      @current_direction = (direction == :left) ? :east : :west
    when :east
      @current_direction = (direction == :left) ? :north : :south
    when :west
      @current_direction = (direction == :left) ? :south : :north
    end
  end

  def walk(steps)
    puts steps
    @stack[@current_direction] += steps.to_i
  end

  def calculate_distance
    distance = (@stack[:north]-@stack[:south]).abs + (@stack[:east]-@stack[:west]).abs
  end
end

bunny_walker = BunnyHQWalker.new

# Traverse through all movements
moves.each do |move|
  move[0] == "L" ? bunny_walker.turn(:left, move) : bunny_walker.turn(:right, move)
  bunny_walker.walk(move[1, move.length])
end

puts "Distance to Easter Bunny HQ is #{bunny_walker.calculate_distance}"