輸出棱形圖案

/**
     * n=1,        n=2          n=3
     *  *           *            *
     *             ***          ***
     *              *          *****
     *                          ***
     *                           *
     * @param n
     */
    public static void print(int n) {
        int sb = 2*n - 1;
        int i = 1;
        //輸出上三角
        while(i < n) {
            int m = 2*i - 1;
            int b = (sb-m)/2;
            while(b > 0) {
                System.out.print(" ");
                b--;
            }
            while(m > 0) {
                System.out.print("*");
                m--;
            }
            i++;
            System.out.println();
        }
        //輸出下三角
        while(n > 0) {
            int m = 2*n - 1;
            int b = (sb-m)/2;
            while(b > 0) {
                System.out.print(" ");
                b--;
            }
            while(m > 0) {
                System.out.print("*");
                m--;
            }
            n--;
            System.out.println();
        }
    }

print(5)

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