UVA11503 Virtual Friends

Description

[problemUrl]: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=27&page=show_problem&problem=2498 [PDF](https://uva.onlinejudge.org/external/115/p11503.pdf) ![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA11503/22196a0b85da544cbb9282738f8363a33f28edf0.png)

Input Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA11503/5479c9917ca9cf83bc83862301aa2ef7e5bbb237.png)

Output Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA11503/58fa3ef5d9c7e6c8d8b6764d58b1bace8a90d1ac.png)