SUBMERGE  Submerging Islands
Vice City is built over a group of islands, with bridges connecting them. As anyone in Vice City knows, the biggest fear of vicecitiers is that some day the islands will submerge. The big problem with this is that once the islands submerge, some of the other islands could get disconnected. You have been hired by the mayor of Vice city to tell him how many islands, when submerged, will disconnect parts of Vice City. You should know that initially all the islands of the city are connected.
Input
The input will consist of a series of test cases. Each test case will start with the number N (1 ≤ N ≤ 10^4) of islands, and the number M of bridges (1 ≤ M ≤ 10^5). Following there will be M lines each describing a bridge. Each of these M lines will contain two integers Ui, Vi (1 ≤ Ui,Vi ≤ N), indicating that there is a bridge connecting islands Ui and Vi. The input ends with a case where N = M = 0.
Output
For each case on the input you must print a line indicating the number of islands that, when submerged, will disconnect parts of the city.
Example
Input: 3 3 1 2 2 3 1 3 6 8 1 3 6 1 6 3 4 1 6 4 5 2 3 2 3 5 0 0 Output: 0 1
hide comments
ramini1996:
20180210 20:44:32
AC in ONE GO !!! Learnt Tarjan's Algorithm for finding Articulation points :) 

sharif ullah:
20171123 08:49:24
this is straightforward AP problem,,,,if u getting WA ,then u just focus on ur implementation,,,,,


amulyagaur:
20171030 06:32:48
Direct AP 

spojabhi:
20171019 21:59:45
@smso


smso:
20170824 19:56:08
I tried to find the articulation points and was able to pass most of the test cases in spojtoolkit except the biggest one with N=10000 and M=3000 (answer=1222, mine=4).


namitp:
20170716 09:21:53
Easy One...


updown:
20170531 22:28:37
I was getting WA but I used this test to debug my code. Here is a test case


kira28:
20170410 12:15:59
This is a classical problem .


anurag_tangri:
20170406 22:23:08
easy problem. learnt Tarjans algorithm :) Last edit: 20170406 22:23:37 

flyingduchman_:
20170227 19:09:26
Learn to find Articulation Points (or Cut Vertices) in a Graph from geeksforgeeks and a tutorial video** first or get yourself submerged Last edit: 20170227 19:10:31 
Added by:  Hector Navarro 
Date:  20130516 
Time limit:  1s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All except: ASM64 
Resource:  MiniMaraton 2013  UCV 