跟踪路径，骑士旅行

到目前为止，我的最短路径方法将在到达目标位置时停止，打印出它沿途所做的一切。 我想知道如何实现父位置，以便我可以打印路径和目标。 这是一项任务。

class Knight attr_accessor :x, :y, :prev_position, :moves def initialize(position) @x = position[0] @y = position[1] @prev_position = nil @moves = [ [-1,-2], [-2,-1], [-2,+1], [-1,+2], [+1,-2], [+2,-1], [+2,+1], [+1,+2]] end def possible move_list = Array.new @moves.each do |moves| x = @x + moves[0] y = @y + moves[1] if x.between?(0,7) if y.between?(0,7) move_list << [x,y] end end end move_list end end def shortest_path(position,goal) paths = Array.new @start_knight = Knight.new(position) until @start_knight.x == goal[0] and @start_knight.y == goal[1] @start_knight.possible.each do |p| paths << p end shifted = paths.shift @start_knight.x = shifted[0] @start_knight.y = shifted[1] puts "[#{@start_knight.x},#{@start_knight.y}]" end end shortest_path([0,0],[7,7])