UVA10454 Trexpression

Description

[problemUrl]: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=16&page=show_problem&problem=1395 [PDF](https://uva.onlinejudge.org/external/104/p10454.pdf) ![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA10454/826cce39b0cdb90eec5bf4cdc734154ad4546e73.png)

Input Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA10454/3e40160156c18a4dc1f0eea384b779c36da3e521.png)

Output Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA10454/730e2887cdc7c1dc763dba5ee78e58550177bc4d.png)