打印空心菱形

<span style="font-size:18px;">/*优化第8个程序，打印空心菱形   *  * * *   **     * *   *  * *   **/public static void main(String[] args) {for (int i = 1; i <= 4; i++) {// 上半部分4行for (int k = 1; k <= 4 - i; k++) {// 第一行3空格，第二行2递减System.out.print(" ");}for (int j = 1; j <= 2 * i - 1; j++) {// 第一行1个*，3*，5*，7*if (j == 1 || j == 2 * i - 1) {System.out.print("*");} else {System.out.print(" ");}}System.out.println();}for (int i = 3; i > 0; i--) {for (int k = 1; k <= 4 - i; k++) {System.out.print(" ");}for (int j = 1; j <= 2 * i - 1; j++) {if (j == 1 || j == 2 * i - 1) {System.out.print("*");} else {System.out.print(" ");}}System.out.println();}}</span>