代码如下：

import java.util.Scanner;public class App13 {public static void main(String[] args) {Scanner scanner = new Scanner(System.in)

;System.out.print("请输入金字塔层数：")

;int n = scanner.nextInt()

;for (int i = n; i >= 0; i--) {for (int k = 0; k < n - i; k++)System.out.print(' ')

;for(int j = 0; j < 2 * i - 1; j++)System.out.print('*')

;System.out.println();}}

}运行结果：