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;

const double pi = 3.14159265358979323846;

#define rep(i, n) for (ll i = 0; i < n; i++)
#define mod 1000000007LL
#define PS(p) cout << setprecision(15) << fixed << p << endl;
#define UNIQUE(v) v.erase(std::unique(v.begin(), v.end()), v.end());
#define ALL(c) c.begin(), c.end()

int main() {
  int A, B;
  cin >> A >> B;
  if ((B % A) == 0) {
    cout << A + B << endl;
  } else {
    cout << B - A << endl;
  }

  return 0;
}