1 121 12321 1234321 123454321 怎样用java中的for循环打印

public class CCC { public static void main(String[] args) { final int Num=5; for(int i=1;i<=Num;i++){ for(int j=1;j<=Num-i;j++){ System.out.print(" "); } for(int j=1;j<=i;j++){ System.out.print(j); }