// editor1
#include<iostream>
using namespace std;
int main()
{
    int a,b;
    cin>>a>>b;
    if(a%2==0 && b%2==0)
    {
        cout<<a+b;
    }
   else if(a%2!=0 && b%2=0)
    {
        cout<<a+b;
    }
    else
    {
        cout<<a-b;
    }
}