Two Longest Paths

题目描述

[problemUrl]: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=226&page=show_problem&problem=2923 [PDF](https://uva.onlinejudge.org/external/118/p11823.pdf) ![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA11823/b1404c09287e621dc26813ecdf51085259966ceb.png)

输入输出格式

输入格式


![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA11823/7bb0d23c8c4e2d6aa69478d7d15028ac4b852ee3.png)

输出格式


![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA11823/db463c5c698c6c86ba561c026ec1d383b4a47f34.png)

输入输出样例

输入样例 #1

3
3 2
1 2
2 3
8 9
1 2
2 3
3 4
5 6
6 7
7 8
2 6
6 3
3 7
4 2
1 2
3 4

输出样例 #1

3
8
4