#include<iostream>
using namespace std;

void calculateResult(int A, int B)
{
    if(A < 0 || B < 0)
    {
        cout<<"Invlaid input";
        return;
    }
    
    if(A % 2 ==0 && B % 2 == 0)
    {
        cout << A * B;
    }
    else if(A % 2 !=0 && B % 2 != 0)
    {
            cout << A  + B;
        
    }
    else
    {
        if (A > B)
        cout << A -B;
        else
            cout<< B - A;
    }
}
int main()
{
    int A,B;
    
    cin>>A;
    cin>>B;
    
    calculateResult(A,B)
    
    return 0;
}