[20-04-26][Self-test 7]Java SumOfRepNum

 1 package test_1_7;
 2 
 3 import java.util.Scanner;
 4 
 5 public class SumOfRepNum {
 6 
 7     public static void main(String[] args) {
 8         
 9         /** 求s = a + aa + aaa + aaaa + aa…a的值，其中a是一个数字。
10          * 例如2+22+222+2222+22222(此时共有5个数相加)，几个数相加有键盘控制。输出结果的形式如：2+22+222=246； */
11 
12         Scanner sc = new Scanner(System.in);
13         System.out.println("请输入第一个小于10的数：");
14         int num = sc.nextInt();
15         System.out.println("请输入相加次数：");
16         int count = sc.nextInt();
17         
18         getSum(num, count);
19         
20     }
21 
22     private static void getSum(int num, int count) {
23 
24         int sum = 0;
25         int temp = 0;
26         
27         for (int i = 0; i < count; i++) {
28             temp += num;
29             num *= 10;
30             sum += temp;
31             if (i == count - 1) {
32                 System.out.print(temp);
33             } else {
34                 System.out.print(temp + " + ");
35             }
36         }
37 
38         System.out.print(" = " + sum);
39         
40     }
41 
42 }