java循环练习不会写

有没有简单的方法解决这个问题，自己写的太复杂了，结果不是想要的结果

这个题主要就是看思维，看规律

import java.util.*;

public class test
{
    public static void main(String[] args){
        Scanner sc=new Scanner(System.in);
        // 读取一个正整数  0-35
        int n=sc.nextInt();
        String[] strArray={"1","2","3","4","5","6","7","8","9","A","B","C","D","E","F","G","H","I","J","K","M","L","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"};
        //因为是倒三角
        //所以for循环是从上到下
        for(int i=n;i>0;i--){
            //发现规律
            //第一行没空格，第二行一个空格，第三行两个空格  和n 之间的关系就是  n-i
            for(int j=0;j<(n-i);j++){
                System.out.print(" ");
            }
            //发现规律
            //第一行2n-1 ,每次少两个
            for(int m=0;m<2*i-1;m++){
                System.out.print(strArray[i-1]);
            }
            System.out.println("");
        }
    }
}

图片太糊了

图片太不清晰了