UVA13132 Laser Mirrors

Description

[problemUrl]: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=871&page=show_problem&problem=5043 [PDF](https://uva.onlinejudge.org/external/131/p13132.pdf) ![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA13132/73430c22549b06eb2eb9e004aba845fb1669a347.png)

Input Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA13132/7dc0a6dbfb099c54d7505033405502bc3f13c396.png)

Output Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA13132/da4c9beaf4eaedde9d7e42b0aa53e457bd4d9513.png)