UVA11834 Elevator

Description

[problemUrl]: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=226&page=show_problem&problem=2934 [PDF](https://uva.onlinejudge.org/external/118/p11834.pdf) ![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA11834/f8073bf428e701413ac957d87eec62e1812701ec.png)

Input Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA11834/78079281153c8cfe53a0ac9daa70c5cdb7c1949b.png)

Output Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA11834/55015720f0d9af268ae4f96fcd34ec91e3453ba3.png)