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
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 

vengatesh15:
20170220 16:19:51
easy one in graph :) 

siddharth_0196:
20161230 10:22:35
Direct implementation of algorithm.


lukaszpolska:
20161227 00:16:39
Is there somebody who had wa and now has ac and can give some tests. I don't know why i have wa. Last edit: 20161227 00:22:19 

gauravm788:
20160824 22:03:48
Plz help...Why am I getting wrong answer..Sub ID (17574745)? My code passes all test cases on spoj toolkit 

avisheksanvas:
20160810 16:00:42
Just the Algorithm. Straight. :) 

sanjay:
20160701 13:23:24
Just finding Articulation points in the given connected graph.Nice revision for graph lover's.Thank's for the author. 
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 