import java.util.Scanner; |
public class Main |
{ |
public static void main(String[] args) |
{ |
Scanner x = new Scanner(System.in); //构造一个SCANNER对象,其传入参数为SYSTEM.IN |
int n = x.nextInt(); //读取一个INT数值 |
int sum = 0 ; |
for ( int i = 1 ; i <= n; i++) |
{ |
int tmp = 1 ; |
for ( int j = 1 ; j <= i; j++) |
tmp *= j; |
sum += tmp; |
} |
System.out.println(sum); |
} |
} |