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++14 (GCC 5.4.1) (judge verdict: Accepted)

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<ll> V;
#define rep(a,j,n) for(ll i=a;i<j;i=i+n )
typedef pair<ll,ll> P;
const ll mod = 1000000007;
const ll INF = 1000000009;
ll i;

int main(){
    ll A,B;
    cin>>A>>B;
    if(B%A)cout<<B-A;
    else cout<<A+B;
    cout<<endl;
}