计算 1！+2！+.......+n!

 1 import java.util.*;
 2 public class Main {
 3     public static void main (String [] args) {
 4         Scanner scan=new Scanner(System.in);
 5         int n=scan.nextInt();
 6         int sum=0;        
 7         for(int i=1;i<=n;i++) {
 8             int p=1;
 9             for(int j=1;j<=i;j++) {
10                 p*=j;    
11             }
12             sum+=p;
13         }
14         System.out.println(sum);
15     }
16 }