java中的for嵌套(一个好例子)

(1)常规的大星

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上面的java程序为

 1 public class daxing {
 2 
 3     public static void main(String[] args) {
 4 
 5         for (int i = 0; i < 5; i++) {
 6             for (int j = 0; j < 5; j++) {
 7                 System.out.print("*");
 8             }
 9             System.out.println();
10         }
11 
12     }
13 
14 }
View Code

(2)

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上面程序打印代码为

方法一

 1 public class daxing {
 2 
 3     public static void main(String[] args) {
 4 
 5         int z = 5;
 6         for (int i = 0; i < 5; i++) {
 7             for (int j = 0; j < z; j++) {
 8                 System.out.print("*");
 9             }
10             System.out.println();
11             z--;
12         }
13     }
14 }
View Code

方法二:(优化一下)

 1 public class daxing {
 2 
 3     public static void main(String[] args) {
 4 
 5         int z = 0;
 6         for (int i = 0; i < 5; i++) {
 7             for (int j = z; j < 5; j++) {
 8                 System.out.print("*");
 9             }
10             System.out.println();
11             z++;
12         }
13     }
14 }
View Code

方法三:(再优化一下)

 1 public class daxing {
 2 
 3     public static void main(String[] args) {
 4 
 5         
 6         for (int i = 0; i < 5; i++) {
 7             for (int j = i; j < 5; j++) {
 8                 System.out.print("*");
 9             }
10             System.out.println();
11         }
12     }
13 }
View Code

 

posted @ 2013-12-01 19:36  天天AC  阅读(569)  评论(0编辑  收藏  举报