（二）、编写空心菱形

 1 import java.util.Scanner;
 2
 3 public class EmptyDiamend11 {
 4 public static void main(String args[]) {
 5 Scanner input = new Scanner(System.in);
 6 System.out.print("請輸入要打印拼成棱形上半個三角形的函數，rows=");
 7 int rows = input.nextInt();
 8 int i, j, k; // 初始化變量
 9 for (i = 1; i <= rows; i++) {
10 for (j = 1; j <= rows - i; j++)
11 System.out.print(" ");
12 for (k = 1; k <= 2 * i - 1; k++)
13 if (k == 1 || k == 2 * i - 1)
14 System.out.print("*");
15 else
16 System.out.print(" ");
17 System.out.println(" ");
18 }
19 for (i = 1; i <= rows - 1; i++) {
20 for (j = 1; j <= i; j++)
21 System.out.print(" ");
22 for (k = 1; k <= 2 * (rows - i); k++)
23 if (k == 1 || k == 2 * (rows - i) - 1)
24 System.out.print("*");
25 else
26 System.out.print(" ");
27 System.out.println(" ");
28 }
29 }
30
31 }

（二）、编写空心菱形