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 (GCC 5.4.1) (judge verdict: Accepted)

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
//大小比較(大)
long long int big(long long int a, long long int b) {
	if (a >= b) {
		return a;
	}
	else {
		return b;
	}
}

//大小比較(小)
long long int small(long long int a, long long int b) {
	if (a >= b) {
		return b;
	}
	else {
		return a;
	}
}

main() {
	long long int a=0,b=0,c=0,n, m, k = 0;
	int str[5],str2[5];
	
	scanf("%d%d%d", &str[0],&str[1],&str[2]);
	
	if (str[0] == str[1]) { printf("%d", str[2]); }
	else if (str[0] == str[2]) { printf("%d", str[1]); }
	else{ printf("%d", str[0]); }
}