Java_5.2 数组应用：*的打印

1五行五列的*

*****
*****
*****
*****
*****

    public static void main(String[] args) {
        for (int i = 1; i <= 5; i++) {
            for (int j = 1; j <= 5; j++) {
                System.out.print("*");
            }
            System.out.println("*");
        }
    }

2.

*
**
***
****
*****

    public static void main(String[] args) {
        for (int i = 0; i < 5; i++) {
            for (int j = 0; j <= i; j++) {
                System.out.print("*");
            }
            System.out.println();
        }
    }

 3.

    *
   **
  ***
 ****
*****

    public static void main(String[] args) {
        for (int i = 0; i < 5; i++) {
            for (int j = 0; j < (5-i-1); j++) {
                System.out.print(" ");
            }
            for (int j = 0; j <= i ; j++) {
                System.out.print("*");
            }
            System.out.println();
        }
    }

 4.

    *
   ***
  *****
 *******
*********

    public static void main(String[] args) {
        for (int i = 1; i <= 5; i++)//正序输出上半部分
        {
            for (int j = 1; j <= 5 - i; j++)
            {
                System.out.print(" ");
            }
            for (int k = 1; k <= i * 2 - 1; k++) {
                System.out.print("*");
            }
            System.out.println();
        }
    }

 6.

   *
  ***
 *****
*******
 *****
  ***
   *

    public static void main(String[] args) {
        int lay;
        lay = 7;//菱形的总长度
        for(int i = 1; i <= (lay+1)/2; i++)//正序输出上半部分
        {
            for(int j = 1; j <=(lay+1)/2-i ; j++)//输出空格
            {
                System.out.print(" ");
            }
            for(int k = 1; k <= i*2-1; k++)
            {
                System.out.print("*");
            }
            System.out.println();//换行
        }
        for(int i =(lay+1)/2-1;i >= 1; i --)//倒序输出下半部分
        {
            for(int j = 1; j <= (lay+1)/2-i; j++)//输出空格
            {
                System.out.print(" ");
            }
            for(int k = (lay+1)/2-i; k <=(lay+1)/2-2+i; k ++)//(lay+1)/2-1即为下半个三角形
            {
                System.out.print("*");
            }
            System.out.println();
        }
    }