用if，else 输出年龄时间段.

 1 import java.util.Scanner;
 2 
 3 public class Exercise {
 4 
 5     public static void main(String[] args) {
 6         
 7         Scanner scan = new Scanner(System.in);
 8         
 9         System.out.println("输入你的年龄");
10 
11         int age = scan.nextInt();
12         
13         if(age>80)
14         {
15             System.out.println("长命百岁");
16             
17         }
18         else if(age>70)
19         {
20             System.out.println("古稀之年");
21         }
22         else if(age>60)
23         {
24             System.out.println("花甲之年");
25         }
26         else if(age>40)
27         {
28            System.out.println("不惑之年");
29             
30         }
31         else if(age>20)
32         {
33             System.out.println("弱冠之年");
34         }
35         else if(age>0)
36         {
37             System.out.println("未成年");
38         }
39         else
40         {
41             System.out.println("输入有误");
42         }
43             
44     }
45 
46 }