Problem:
Score : 100 points

Problem Statement

You are given three integers, A, B and C.

Among them, two are the same, but the remaining one is different from the rest.

For example, when A=5,B=7,C=5, A and C are the same, but B is different.

Find the one that is different from the rest among the given three integers.

Constraints

-100 \leq A,B,C \leq 100

A, B and C are integers.

The input satisfies the condition in the statement.

Input

Input is given from Standard Input in the following format:

A B C

Output

Among A, B and C, print the integer that is different from the rest.

Sample Input 1

5 7 5

Sample Output 1

7

This is the same case as the one in the statement.

Sample Input 2

1 1 7

Sample Output 2

7

In this case, C is the one we seek.

Sample Input 3

-100 100 100

Sample Output 3

-100

Solution in C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
public class Hello{
    public static void Main(){
        string[] input = Console.ReadLine().Split(' ');
        int[] num = new int[3];
        
        for(int x = 0;x < 3;x++){
            num[x] = int.Parse(input[x]);
        }
        for(int y = 0;y < 2;y++){
            for(int z = y + 1;z < 3;z++){
                if(num[y] == num[z]){
                    Console.WriteLine(num[3 - y - z]);
                    break;
                }
            }
        }
    }
}