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: Wrong Answer)

#include <stdio.h>

#define SIZE 50

int main(int argc, char *argv[]) {
  int h, w;
  scanf("%d %d\n", &h, &w);
  char map[SIZE][SIZE];
  for (int i = 0; i < h; ++i) {
    scanf("%s\n", map[i]);
  }
 
  for (int i = 0; i < h; ++i) {
    for (int j = 0; j < w; ++j) {
      if (map[i][j] == '.') {
        int c = 0;
        if (0 < i) {
          if (map[i - 1][j] == '#') ++c;
          if (j < w - 1 && map[i - 1][j + 1] == '#') ++c;
          if (0 < j && map[i - 1][j - 1]== '#') ++c;
        }
        if (j < w - 1 && map[i][j + 1] == '#') ++c;
        if (0 < j && map[i][j - 1]== '#') ++c;
        if (i < h - 1) {
          if (map[i + 1][j] == '#') ++c;
          if (j < w - 1 && map[i + 1][j + 1] == '#') ++c;
          if (0 < j && map[i + 1][j - 1]== '#') ++c;
        }
        map[i][j] = c;
      }
    }
  }
  for (int i = 0; i < h; ++i) {
    for (int j = 0; j < w; ++j) {
      printf("%c", map[i][j]);
    }
    printf("\n");
  }
  return 0;
}