java循环嵌套练习

一·二重

(1)输出结果如下:
1
1 2
1 2 3
1 2 3 4
1 2 3 4 5
1 2 3 4 5 6
1 2 3 4 5 6 7
1 2 3 4 5 6 7 8
1 2 3 4 5 6 7 8 9

public class Test {
    public static void main(String[] args){
        int i,j,;
        for(i = 1;i <= 9;i++){
            for(j = 1;j <= i;j++){
                System.out.print(j);
            }
            System.out.println();
        }
    }
}

(2)输出结果如下:

9 8 7 6 5 4 3 2 1
8 7 6 5 4 3 2 1
7 6 5 4 3 2 1
6 5 4 3 2 1
5 4 3 2 1
4 3 2 1
3 2 1
2 1
1

(3)

1 2 3 4 5 6

1 2 3 4 5

1 2 3 4

1 2 3

1 2

1

public class Test {
    public static void main(String[] args){
        int i,j,m,n;
        for(i = 1;i <= 6;i++){
            for(j = 1;j + i <= 7;j++){
                System.out.print(j);
            }
            System.out.println();
        }
    }
}

二·三重

public class He {
    public static void main(String[] args){
        int i,j,m;
        for(i = 1;i <= 6;i++){
            for(j = 1;j + i <= 6;j++){
                System.out.print(" ");
            }
            for(m = i;m > 0;m--){
            System.out.print(m);
            }
            System.out.println(" ");
        }

    }
}