说明：  自己编的华容道游戏。对用户的上、下、左、右命令进行识别，并提供相应的备选子，在用户输入确认命令后，完成棋子的移动。显示，welcome和所用步数。
(Huarong own game series. To users, down, left and right commands to identify and provide appropriate alternative child, in the confirmation order entered by the user after the completion of the movement of pieces. Show, welcome, and the use of steps.)