利用java画菱形

package xiaojie;

public class liu {

public static void main(String[] args) {    // TODO Auto-generated method stub    for(int a=1;a<=4;a++)    {      for(int b=1;b<=4-a;b++)             System.out.print(" ");        for(int c=1;c<=a*2-1;c++)             System.out.print("*");            System.out.println();    }    for(int d=3;d>=1;d--)    {        for(int b=1;b<=4-d;b++)            System.out.print(" ");        for(int c=4-d;c<=2+d;c++)             System.out.print("*");            System.out.println();    }}}