UVA547 DDF

Description

[problemUrl]: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=7&page=show_problem&problem=488 [PDF](https://uva.onlinejudge.org/external/5/p547.pdf) ![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA547/c6d8a3bf105a4101bb4e47d9a42a2c2bfc84f519.png)

Input Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA547/c6813e8ef6af2573f7d5d9c9e84526154ef4cf66.png)

Output Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA547/d1e43bfb9cb62bd67e37e481f895bb42791948bb.png)