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.


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).


Print the length of the longest path on one line.


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sarvesh_19: 2016-06-16 21:44:07

famous graph problem (easy). N<=10000 array repn giving RTE and TLE...use adjacency list *only trick in this q*.

praval_singhal: 2016-05-19 16:48:16

I submitted the same code 1 hr ago. got WA. Now AC. what the F :P

Shreyans: 2016-04-13 12:46:58

Last edit: 2016-04-13 22:43:12
Ram: 2016-03-31 22:12:13

Finally got AC..!! Got WA repeatedly while using start node as 1. Changed the start node from 1 to last node and it got accepted. Please notify if there is anything wrong in my code.

sharif ullah: 2016-03-14 09:47:06

just find the diameter of a tree.2 bfs.needed!!!!!!!!!!!!

rohit123456: 2016-03-05 12:28:44

done in a single dfs

newbie: 2016-01-30 14:18:18

answer is 5

newbie: 2016-01-30 14:17:44

simple dfs accepted in 0.00 s
a test case to check:
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dwij28: 2016-01-15 06:29:00

Did it by using bfs twice, what is the dfs way of doing it ? If anyone could please provide some helpful link for solving it with dfs..

dark_lord1: 2015-12-26 00:12:43

Using a 2D matrix of type char to store edge information gives runtime error..But using adjacency list to store graph give AC....How can the 2D matrix possibly exceed memory available?? Costed me 2 RE. :(

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