2017-11-11

Program：

求解:1+2!+3!+...+n!的和。

 

代码如下：

 

 1 /*
 2  * 求解:1+2!+3!+...+n!的和
 3  * 
 4  * Date Written:2017-11-11
 5  * 
 6  * */
 7 
 8 package test;
 9 
10 import java.util.Scanner;
11 
12 public class TestDemo {
13     
14     public static void main(String args[]) {
15         
16         int n = 0;                //接受用户输入，定义求解到最大数的阶乘
17         Scanner scan = new Scanner(System.in);
18         
19         System.out.println( "Please input the value of n:" );
20         n = scan.nextInt();       //取得用户输入
21         
22         System.out.println( "The result is " + getResult(n) );
23         
24         scan.close();            //关闭scan;
25             
26     }
27     
28     //求解阶乘
29     public static int getResult(int n) {
30         
31         int sum = 0;             //存储最终结果
32         int temp = 1;            //当前i的阶乘
33         for( int i = 1; i <= n; i++) {
34             
35             temp *= i;
36             sum += temp;
37         }
38         
39         return sum;
40     }
41     
42     
43 }