"Guess Number®" also called "bulls and cows". It is an old-breaking paper and pencil game. When the game starts, it randomly generates 4 digit numbers from number 0 to number 9, all 4 digit are different. The 4 random numbers are what you need to figure out at end of the game. First you have to guess 4 numbers to start your supposition. After that there’s a hint for you to amend the first supposition. There are servel chances for you to amend your suppostion base on the hint till you find the right answer. If your suppostion shows right number and in the right position, you will gain an A. If your suppostion shows right numbers in the wrong positions, you will gain B.Example:The random 4 figures: 1234Your suppose: 3024Hint: 1A2B (the “A” refers to “4”, and the “B” refers to “2” or “3”.)The "A" and "B" is HINT, Get 4 "A" to win the game.