#include <iostream>

using namespace std;

int main() {
    int n;
    cin >> n;

    string str_n = to_string(n);
    int result = 1;
    for (char c : str_n) {
        if (c == '-') {
            result *= -1;
            continue;
        }
        result *= (c - '0');
    }
    cout << result << endl;

    return 0;
}