#include <iostream>
using namespace std;

int Factorial(int n){
    if(n == 0 || n == 1)
        return 1;
        
    return n * Factorial(n-1);
}

void CalculateFactorial(int n){
    if(n == 0 || n == 1){
        cout << "1";
        return;
    }
    
    int ans = Factorial(n);
    cout << ans;
}

int main() {
    int n;
    
    cout << "Enter a number: ";
    cin >> n;
    
    cout << "Factorial of " << n << ": ";
    CalculateFactorial(n);

    return 0;
}