用java打印趣味三角

import java.util.Scanner;

public class P1144 {

    public static void main(String[] args) {
        int i,j,n,k=1;
        int a[][]=new int[100][100];
        Scanner reader =new Scanner(System.in);
        n=reader.nextInt();
        for(i=1;i<=n;i++){
            for(j=1;j<=i;j++){
                a[i+1-j][j]=k;
                k=k+1;
            }
        }
        for(i=1;i<n;i++){
            System.out.println();
            for(j=1;j<=n+1-i;j++){
                System.out.print(" "+a[i][j]);
            }
        }

    }

}