Find the Different Ball

Problem Description

There are three balls A, B, C. They are the same in size and shape, and exactly one of them has a different weight from the other two. Find this different ball.

Input Format

The input gives 3 positive integers on one line, corresponding in order to the weights of balls A, B, C.

Output Format

Output on one line the unique different ball, which is one of A, B, C.

Sample Input 1

1 2 2

Sample Output 1

A

Sample Input 2

3 3 4

Sample Output 2

C

Constraints

$1 \le$ each ball's weight $\le 10^9$. It is guaranteed that among the three balls exactly one has a different weight from the other two.

Hint

• Two comparisons are enough: first compare a and b — if they are equal, who is the answer? If not, one more comparison decides who the answer is.
• The output is an uppercase letter.
• Verify with the sample: 3 3 4 → C.