UVA139 Telephone Tangles

Description

[problemUrl]: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=3&page=show_problem&problem=75 [PDF](https://uva.onlinejudge.org/external/1/p139.pdf) ![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA139/bb0094dded62ac285619834c8413a4e40fa88455.png)

Input Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA139/6e97facc0864cb51d15785ca7399dcbfd1cd60e7.png)

Output Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA139/9c3f0a22b82029463a70f848df60288e63cc1568.png)