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 <iostream>
#include <vector>
#include <string>
#include <cmath>
#include <set>
#include <algorithm>
#include <array>
#include <complex>
#include <string>
#include <utility>
#include <map>
#include <queue>
#include <list>
#include <functional>
#include <numeric>
#include <stack>
#include <tuple>

using namespace std;
int dx[4] = { -1,0,1,0 };
int dy[4] = { 0,1,0,-1 };
const int INF = 100000000;
const long long LINF = 1000000000000000000;
const int MOD = (int)1e9 + 7;
const double EPS = 1e-6;
using pii = std::pair<int, int>;
using ll=long long;  
using pLL = std::pair<ll, ll>;

#define SORT(v) std::sort(v.begin(), v.end())
int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);
    int a,b;
    cin >> a >> b;
    if(b%a==0){
        cout << a+b<<endl;
    }else{
        cout<<b-a <<endl;
    }
    
    return 0;
}