UVA994 POP

Description

[problemUrl]: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=11&page=show_problem&problem=935 [PDF](https://uva.onlinejudge.org/external/9/p994.pdf) ![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA994/2d669aef929f472c0acf656a2d630d0b93cfa50b.png)

Input Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA994/0e3f92c7b0d19b59382727fd7cd11a57fcf04362.png)

Output Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA994/0edbe91d366fc63950c9c2f9e8b15dd3284f3ed5.png)