PT07Z - Longest path in a tree


You are given an unweighted, undirected tree. Write a program to output the length of the longest path (from one node to another) in that tree. The length of a path in this case is number of edges we traverse from source to destination.

Input

The first line of the input file contains one integer N --- number of nodes in the tree (0 < N <= 10000). Next N-1 lines contain N-1 edges of that tree --- Each line contains a pair (u, v) means there is an edge between node u and node v (1 <= u, v <= N).

Output

Print the length of the longest path on one line.

Example

Input:
3
1 2
2 3

Output:
2

hide comments
scorpion_ajay: 2017-01-31 12:58:14

did it with both bfs and dfs, try both :)

Chisty: 2017-01-02 19:56:23

I got accepted with Adjacency Matrix in C++. bool graph[10001][10001] is okay as global variable.

hasan356: 2016-12-29 08:15:30

learned bfs!!

rez_wan_28: 2016-12-18 10:44:44

simple bfs..

cjycjy: 2016-11-10 04:49:01

Longest path dosen't stand for the deepth of the tree. So naive was I :(

jawad_cs: 2016-11-06 08:45:58

Do not use Adjacency Matrix ull get a tle, use Adjacency List.

arpitscoding: 2016-09-26 17:14:54

f you! 5th test case.

rkasat: 2016-09-26 00:06:57

one bfs to find the farthest node. second bfs to find the longest path. AC in one go!

Kuldeep Fouzdar: 2016-09-25 19:02:27

CLRS(3rd edition) #22.2-8

vishalsingh: 2016-08-20 17:02:42

how one knows which test case my solution fails


Added by:Thanh-Vy Hua
Date:2007-03-28
Time limit:0.5s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
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Resource:Co-author Amber