#include <iostream>
using namespace std;
void calculateResult(int A,int B)
{
    if(A<0||B<)
    {
        cout<<"Ivalid input";
        return;
    }
}
   if(A%2==0&&B%2==0)
   {
       cout<<A*b;
   }
   if(A%2!=0&& B%2 !=0)
   {
       cout<<A+B;
    else
        cout<<B-A;
   }
}
int main()
{
    int A,B;
    cin>>A;
    cin>>B;
    calculateResult(A,B)
    return 0;
}