题：如下所示，根据输入行数打印字母，字母个数呈等差数列递减，行首空格数呈等差数列递增：

请输入行数
5
EEEEEEEEE
 DDDDDDD
  CCCCC
   BBB
    A

请输入行数
9
IIIIIIIIIIIIIIIII
 HHHHHHHHHHHHHHH
  GGGGGGGGGGGGG
   FFFFFFFFFFF
    EEEEEEEEE
     DDDDDDD
      CCCCC
       BBB
        A

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入行数");
        int number = sc.nextInt();
        char character = (char) ('A' + number - 1);
        for (int i = number; i >= 1; i--) {
            for (int j = 0; j < number - i; j++) {
                System.out.print(" ");
            }
            for (int k = 0; k < 2 * i - 1; k++) {
                System.out.print(character);
            }
            character--;
            System.out.println();

        }
        sc.close();
    }