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
Himanshu Sharma: 2016-08-14 03:12:59

single dfs, my 50th ;-[]

Surbhi: 2016-08-07 17:31:32

Why is adjacency matrix not working?

saurabh789: 2016-07-11 13:10:07

use dfs two times first time to find a node "s" which is at max distance from any child node, next time use "s" as starting node and find length of longest path

sumit suthar: 2016-07-07 14:51:28

double dfs easy one..

Suryansh Agnihotri: 2016-07-01 12:28:32

It is having weak test cases , one of my wrong solution got accepted.

ajay_raj: 2016-06-29 19:44:23

Last edit: 2016-07-01 03:48:57
kunal todi: 2016-06-25 11:56:21

Can anyone help me.I got TLE..it runs till 5th test case...

pratika: 2016-06-24 11:57:17

WA repeatedly, removed memset and got ac :O

baadshah_: 2016-06-22 21:11:56

Finally AC ! did it using single DFS!!dont use matrix !!USE adj List

Last edit: 2016-06-22 21:13:15
demigod_luffy: 2016-06-18 09:00:36

My 50th one!!! one dfs + dp :)


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