Problem:
Score : 100 points

Problem Statement

You are given positive integers A and B.

If A is a divisor of B, print A + B; otherwise, print B - A.

Constraints

All values in input are integers.

1 \leq A \leq B \leq 20

Input

Input is given from Standard Input in the following format:

A B

Output

If A is a divisor of B, print A + B; otherwise, print B - A.

Sample Input 1

4 12

Sample Output 1

16

As 4 is a divisor of 12, 4 + 12 = 16 should be printed.

Sample Input 2

8 20

Sample Output 2

12

Sample Input 3

1 1

Sample Output 3

2

1 is a divisor of 1.

Solution in C (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<stdio.h>
int n,m,i,k[30],a[30][30],f,flag[30],h,count;
int main(void){
    scanf("%d%d",&n,&m);
    for(i = 0;i < n;i++){
    scanf("%d",&k[i]);
    for(f = 1;f<k[i];f++){
        scanf("%d",&a[i][f]);
    }
    }

    for(i=0;i<n;i++){
        for(f=1;f<k[i];f++){
            flag[a[i][f]] += 1;
        }
        
    }
    for(i=1;i<m;i++){
        if(flag[i] == n){
            count +=1;
        }
    }
    
printf("%d",count);
return 0;
}