UVA11673 Enemy at the Gateway

Description

[problemUrl]: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=78&page=show_problem&problem=2720 [PDF](https://uva.onlinejudge.org/external/116/p11673.pdf) ![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA11673/a88478b6f9fc951a95d9fca57ecb5d76239d5500.png)

Input Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA11673/8334e1a1d740e870b17c8df42ad16fd4fe07910d.png)

Output Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA11673/f33770df897c57f78313ad6425062d8505c92ae2.png)