UVA681 Convex Hull Finding

Description

[problemUrl]: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=8&page=show_problem&problem=622 [PDF](https://uva.onlinejudge.org/external/6/p681.pdf) ![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA681/4aa7a8eeb706b263ca91acbaadfb7aa437160df1.png)

Input Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA681/0cfb4febd26012824553f71f2e61ee4204c9146e.png)

Output Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA681/94ec618fd5cd3a8624d4e9cc85cd9ae689020d63.png)