#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b;
  cout << "enter the first number = " << endl;
  cin >> a;
  cout << "enter the second number = " << endl;
  cin >> b;
  if (a >= 1 && a <= 20 && b >= 1 && b <= 20) {
    cout << "The result = " << a * b;
  } else
    cout << "-1";
}
