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
ramjeet saran: 2015-08-22 14:25:59

not a binary tree, cost me 3 WA

Khanh Ninh: 2015-08-11 14:35:51

Dynamic Program + DFS , Advanced Solution.

mohit: 2015-08-04 20:54:44

DFS! diameter of a tree . http://www.geeksforgeeks.org/diameter-of-a-binary-tree/

sameer Hussain: 2015-07-30 22:00:44

is it a binary tree or any random tree ??

Nitesh Tiwari: 2015-07-25 23:25:25

Answer for the below test case is 6, spojtoolkit is showing 5, I got it accepted with 6.
15
1 2
2 3
1 11
3 11
4 11
4 5
5 6
5 7
6 7
4 12
8 12
9 12
8 10
9 10

Krzysztof Strojny: 2015-07-22 11:03:16

This can be done in in one loop over vertices, take advantage that this is a tree, no need for BFS or DFS

psionic: 2015-07-12 23:55:11

DFS and DFS :D

Ankur Arora: 2015-07-12 21:57:35

kindly
d
o
n
t
see
comments

for
solving this
you should know
famous
graph
algorithms
.
.
.
.
.
still
.

.
.

santamaria: 2015-07-03 17:20:14

Ohh yeah (BFS & BFS) :D

Deeksha: 2015-06-29 12:25:03

take 1 as start node..

Last edit: 2015-06-29 20:39:20

Added by:Thanh-Vy Hua
Date:2007-03-28
Time limit:0.5s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ERL JS-RHINO NODEJS PERL6 VB.NET
Resource:Co-author Amber