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.


1 2
2 3


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xopxop1: 2017-08-18 13:20:05

Solution to this and many other tasks are here

sharma96: 2017-08-15 22:05:04

Can anyone please tell how to handle this test case:
1 2
1 3
2 4

The question specifies N-1 lines will be input,but in this test case there are N lines.

Last edit: 2017-08-15 22:07:57
Shantanu Banerjee: 2017-08-08 08:44:15

Simple Double DFS!

sunidhi: 2017-08-04 06:17:12

@anuraag19 spoj won't allow us to see your solution.use some other platform to share your code.

anuraag19: 2017-08-02 18:51:15

does anybody know why i am getting runtime error?,anuraag19/

Last edit: 2017-08-02 18:52:12
karthik_vg: 2017-07-18 13:55:21

dfs + memorization ;)

sagnik_66: 2017-07-05 10:48:57

Solved using single DFS, this helped :

phben: 2017-07-04 03:24:22

@prashant2018 How to see the test cases? Aren't they hidden?

ashwani0605: 2017-06-21 06:52:03

Some of the answer in SPOJ toolkit are wrong, so verify on your own

sandeep_4141: 2017-06-14 10:27:13


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