#include<iostream>
using namespace std;
int main()
{
    int n;
    cin>>n;
    if(n<=0)
    {
        cout<<"Invalid input";
    }
    else if(n>12)
    {
        cout<<"Overflow occurred";
    }
    else
    {
        long long factorial=1;
        for(int i=1;i<=n;i++)
        {
            factorial*=1;
        }
        cout<<f
    }
}