How to create a nested loop that gives output as following [关闭]

Question

嵌套循环给出：

0,3
0,2
0,1
1,4
1,3
3,6
3,5
3,4
4,7
4,6
6,7

int x;
int y;
outerloop:
for (x = 0; x <= 7;x=y ) {
    for (y = x + num; y <= 7; y--)