UVA512 追踪电子表格中的单元格 Spreadsheet Tracking

Description

[problemUrl]: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=7&page=show_problem&problem=453 [PDF](https://uva.onlinejudge.org/external/5/p512.pdf) ![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA512/10a1727a72d40db4b10c320362350f78438e8cc7.png)

Input Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA512/1e89acba1f557aefb6123ad850fa0570ce6ee7b3.png)

Output Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA512/2aee08246e2460cf68086abeff5472d50069f607.png)