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>
#include <vector>
typedef long long ll;
#define  rep(i,a,b)for(long long i=a;i<b;++i)
#define  rrep(i,a,b)for(int i=a;i>=b;--i)
#define  yesno(flag)if(flag)cout<<"Yes"<<endl; else cout<<"No"<<endl;
using namespace std;
const ll INF=200000000000005LL;
const ll r197=1000000007;
typedef pair<ll,ll>P;
typedef pair<P,P>Pa;
bool Inframe(int a,int b,int c,int d,int h,int w){
	if(a+b>=0&&a+b<h&&c+d>=0&&c+d<w)return true;
	return false;
}
struct edge{
	ll x;
	ll y;
	bool operator<(const edge& e)const{
		return x+y<e.x+e.y;
	}
	bool operator>(const edge& e)const{
		return x+y>e.x+e.y;
	}


};
struct road{ll cost;int to;};
int n;
int a,b;
int t=0;
int main() {
	cin>>a>>b;
	if(b%a==0)cout<<a+b<<endl;
	else cout<<b-a<<endl;

	return 0;
}