UVA12070 Invite Your Friends

Description

[problemUrl]: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=242&page=show_problem&problem=3222 [PDF](https://uva.onlinejudge.org/external/120/p12070.pdf) ![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA12070/a07ee048ab8f5cadc14a319f699c31e92462adda.png)

Input Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA12070/e5292cd834b526215369b31872af3ac01a87f284.png)

Output Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA12070/e4dadc942febd7ba1ce2b0502dab7b3c34a99c19.png)