///ДСНП, която извежда N! = 1*2*3…..*N
#include <iostream>
using namespace std;
int main(){

    long long f=1, input, counter=1;
    ///vuvejdame inputa
    cin>>input;
    ///suzdavam cikul v koito sravnqvam broqch i input
    while(counter<input+1){

    f = f*counter;
    counter++;
    }
cout<<"N!= "<<f<<endl;


return 0;
}