#include <iostream>
using namespace std;
void calculateResult(int A,int B) {
    if(A<0||B<0) {
        cout<<"Inavalid input";
        return 0;
    }
    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;
}