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 N1 lines contain N1 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:
20170131 12:58:14
did it with both bfs and dfs, try both :) 

Chisty:
20170102 19:56:23
I got accepted with Adjacency Matrix in C++. bool graph[10001][10001] is okay as global variable. 

hasan356:
20161229 08:15:30
learned bfs!!


rez_wan_28:
20161218 10:44:44
simple bfs..


cjycjy:
20161110 04:49:01
Longest path dosen't stand for the deepth of the tree. So naive was I :( 

jawad_cs:
20161106 08:45:58
Do not use Adjacency Matrix ull get a tle, use Adjacency List. 

arpitscoding:
20160926 17:14:54
f you! 5th test case. 

rkasat:
20160926 00:06:57
one bfs to find the farthest node. second bfs to find the longest path. AC in one go! 

Kuldeep Fouzdar:
20160925 19:02:27
CLRS(3rd edition) #22.28 

vishalsingh:
20160820 17:02:42
how one knows which test case my solution fails

Added by:  ThanhVy Hua 
Date:  20070328 
Time limit:  0.5s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
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Resource:  Coauthor Amber 