#include <iostream>
using namespace std;
int main() {
    int calculateArea(int length, int width) {
        return length * width;
    }
        int main() {
            int length , width;
            cin >> length >> width;
   
    if(length <= 0 || width <= 0) {
     cout << "Invalid input";
    }
    else {
        cout << calculateArea(length,width);
    }
    return 0;
}