Find the connected features of the Find-the-connected-component-in-the-undirected-graph graph summary

Please find out the number of connected features in the graph.

Each node in the diagram contains 1 tags and a list of its neighbors. (a linked node (or node) of a non-graph is a sub-graph where any two vertices are connected by a path and are not connected to other vertices in the super graph.) ）

Sample Example

Given diagram:

A------B  C \     |  |   \    |  |   \   |  |    \  |  |      D   E

Return {A,B,D}, {C,E} . There are 2 connected elements, namely{A,B,D}, {C,E}

Idea: To tell the truth, Lintcode translation I did not understand what the meaning, of course, do not know how to do. To be exact, this problem should be called finding the maximal connected sub-graphs in undirected graphs, and the algorithm used is breadth-first search. Here is a comparison of breadth-first search and depth-first search algorithms, which, incidentally, is reviewed;

http://blog.csdn.net/andyelvis/article/details/1728378

Of course the code is also I learn others, the source attached http://www.jiuzhang.com/solutions/find-the-connected-component-in-the-undirected-graph/

1 /**2 * Definition for undirected graph.3 * Class Undirectedgraphnode {4 * int label;5 * arraylist<undirectedgraphnode> neighbors;6 * Undirectedgraphnode (int x) {label = x; neighbors = new arraylist<undirectedgraphnode> ();}7  * };8  */9  Public classSolution {Ten     /** One      * @paramnodes A array of undirected graph node A      * @returna connected set of a undirected graph -      */ -      PublicList<list<integer>> Connectedset (arraylist<undirectedgraphnode>nodes) { the         //Write Your code here -         intm =nodes.size (); -Map<undirectedgraphnode,boolean> visited =NewHashmap<>(); -          for(Undirectedgraphnode node:nodes) { +Visited.put (node,false); -         } +list<list<integer>> result =NewArraylist<>(); A          for(Undirectedgraphnode node:nodes) { at             if(visited.get (node) = =false){ - BFS (node,visited,result); -             } -         } -         returnresult; -     } in      Public voidBFS (Undirectedgraphnode node,map<undirectedgraphnode,boolean> visited,list<list<integer>>result) { -list<integer> row =NewArraylist<>(); toqueue<undirectedgraphnode> queue =NewLinkedlist<>(); +Visited.put (node,true); - queue.offer (node); the          while(!Queue.isempty ()) { *Undirectedgraphnode U =Queue.poll (); $ Row.add (U.label);Panax Notoginseng              for(Undirectedgraphnode v:u.neighbors) { -                 if(Visited.get (v) = =false){ theVisited.put (V,true); + Queue.offer (v); A                 } the             } +         } - collections.sort (row); $ result.add (row); $     } -}

Find the connected features of the Find-the-connected-component-in-the-undirected-graph graph summary