Кирилл Деменев

/* package whatever; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
    public static void main (String[] args) throws java.lang.Exception
    {
        Scanner in = new Scanner(System.in);

        int n; n = in.nextInt();
        int F = 1; int[] f = new int[n];

        for (int i = 1; i <= n; i++) {
            F = i * F;
        }

        System.out.println(F);
    }
}