#include <iostream>
using namespace std;

void calculate Result(int A,int B)
{
    if(A<0||B<0)
{
    cout<<"Invalid 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;
    
    calculate Result(A,B);
    
    return 0;
}
}