1.产生一个随机的不重复的4位数 比如 3645（玩家并不知道这个数字）

2.由玩家开始来猜这个数字，每猜完一次，系统给出相应的提示。如果猜对了，游戏结束。如

果猜错了，继续游戏，同时给出一些有用的信息。

比如猜 3654，则给出提示：2A2B， 如果猜 1234，则给出提示：0A2B

3.需要计时，在游戏过程当中及时的显示所用的时间。当游戏结束之后，显示总共用时多少。-1 generates a random four-digit non-repetition of such 3645 (the players do not know this number) 2. Started by the player to guess the figure, each guess once finished, the system gives the corresponding prompt. If you guess right, the game ends. If you guess wrong, to continue the game, and gives some useful information. For example suppose 3654, then give tips: 2A2B, if you guessed 1234, gives tips: 0A2B 3. Need time during the game in which timely display the elapsed time. When the game ends, the display when a total number.