import java.util.Scanner;
public class  HelloWorld {
	
	//计算1!+2!+3!+4!+5!
	public static void main(String[] args) {
		int num = 5;
		int i = 1;
		int sum = 0;
		int ret = 1;
		while(i <= num)
		{
			ret *= i;
			i++;
			sum+=ret;
		}
		System.out.println(sum);
	}
	
	//计算1!+2!+3!+4!+5!
	public static void main5(String[] args) {
		int num = 1;
		int sum = 0;
		while(num <= 4) {
			int i = 1;
			int ret = 1;
			while(i <= num) {
				ret *= i;
				i++;
			}
			sum += ret;
			num++;
		}
		System.out.println(sum);
	}
	
	public static void main4(String[] args) {
		boolean flg = true;
		if(!flg == false)
		{
			System.out.println("hahahha");
		}
	}
	
	public static void main3(String[] args) {
		Scanner scan = new Scanner(System.in);
		int a = scan.nextInt();
		System.out.println(a);
	}
	
	public static void main2(String[] args) {
		byte b = 10;
		byte c = 20;
		int x = -1;
		x = x >> 4;
		//byte d = b+c;
		//byte d = （byte)b+c;
		//System.out.println(d); //err
		System.out.println(b+c);
		System.out.println(x);
		
	}
	
	public static void  main1(String[] args) {
		int a = 10;
		int b = 20;
		
		System.out.println("HelloWorld");
		System.out.println(a + b + "hhh");//30hhh
		System.out.println("hhh" + a + b);//hhh1020
		
	}
}