UVA688 Mobile Phone Coverage

Description

[problemUrl]: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=8&page=show_problem&problem=629 [PDF](https://uva.onlinejudge.org/external/6/p688.pdf) ![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA688/7e10937e57a7fd7936eb157029f15eceb151145e.png)

Input Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA688/d0f58b0b31fe34fb473adde2f72ab5b0db166a5c.png)

Output Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA688/231d0c0774ffb0fc6200b4b117d6b80024d29d6a.png)