Counting Triangles

题目描述

[problemUrl]: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=242&page=show_problem&problem=3227 [PDF](https://uva.onlinejudge.org/external/120/p12075.pdf) ![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA12075/248d9d633372dc8b35931ba62f08299669035131.png)

输入输出格式

输入格式

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA12075/69241c8a937f04e49f024babb9476232b97f451c.png)

输出格式

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA12075/8809bd35cb37ab1420722d50af3bd77cb04e855c.png)

输入输出样例

输入样例 #1

1 1
1 2
0 0

输出样例 #1

Case 1: 4
Case 2: 18