Problem 28562 --线图

28562: 线图

Time Limit: 3 Sec  Memory Limit: 128 MB
Submit: 1  Solved: 1
[Submit][Status][Web Board][Creator:][下载FPS0元][添加到购物车][下载测试数据0元][461kb]

Description

Input

Output

Sample Input

5 3
1 2
2 3
2 5
3 4

Sample Output

5

HINT

Source

[Submit][Status]