import java.util.Scanner;

public class Lei {

public static void main(String args[])

{

int i=1;

int product=1;

Scanner input =new Scanner(System.in);

System.out.print("请输入基数:");

int n=input.nextInt();

while(n>=i)

{

     product*=i;

    i++;

}

System.out.println(n+"的阶乘为："+product);

}

}