import java.util.Scanner;
class TestMul{
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		System.out.println("请输入要求的数阶乘:");
		int num = sc.nextInt();
		int result=1;
		for(int i=1;i<=num;i++){
			result *= i;
		}
		System.out.println("result =" + result);
	}
}

import java.util.Scanner;
class TestFactorial{
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		System.out.println("请输入要求的数阶乘:");
		int num = sc.nextInt();
		System.out.println(factorial(num));
	
	}
	public static int factorial(int n){
		if(n == 1){
			return 1;
		}
		return n*factorial(n-1);
	}
}