• The computer selects a random number between 1 and 9999. Your aim is to guess that number in the least number of steps.
• Enter a number between and including 1 and 9999.
• The computer verifies the number and displays the result in terms of bulls and cows.
• A Bull indicates that the digit in your number and the computer's number are in the correct position.
• A Cow indicates that the digit is present in the number, but is not in the right position.

Examples:
Computer's number is 2347.
You enter 1267.
The digits 2 and 7 are present in the both the numbers. 7 is in the exact position. So, it is a bull. 2 is not in the same position... so it is a cow.

Computer's number is 5368.
You enter 2358.
3, 8 are in the same position - 2 bulls.
5 is in a different position - 1 cow.

Computer's number is 2268.
You enter 1328.
8 is in the same position - 1 bull.
2 is in a different position - 1 cow.

You enter 2328.
2 (1st position) and 8 - 2 bulls.
2 (3rd position) - 1 cow.

Computer's number - 0023.
You enter 123.
3 bulls and 0 cows.

You enter 230.
1 bull and 3 cows.