UVA712 S树 S-Trees

Description

[problemUrl]: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=9&page=show_problem&problem=653 [PDF](https://uva.onlinejudge.org/external/7/p712.pdf) ![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA712/06124389d0356456dc7c53ca0e5e30a32757570d.png)

Input Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA712/c7143978c1bdeb79fbe20cb0a5cda4d31409bafa.png)

Output Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA712/63397dbb644dba084be32b334dcba1b768b31534.png)