UVA12460 Careful teacher

Description

[problemUrl]: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=279&page=show_problem&problem=3891 [PDF](https://uva.onlinejudge.org/external/124/p12460.pdf) ![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA12460/8349fe358c83d9adf57cd76704a1f7f5ac60590d.png)

Input Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA12460/cb5d4d8f65d39d40cbdc19da0226880c18ec2cd6.png)

Output Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA12460/caa3c66747bcf7a1cdbe8d9b1bae79063adb274e.png)