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Breadth First Search Implementation in Java


Breadth First Search Implementation in Java

For Graph Class Design and DFS implementation please refer to below link:-

depth-first-search-implementation-in-java


 
/*

1. Pick a vertex.
2. Get Adjacent Vertex.
3. Insert in queue ( at tail)
4. Remove vertex from queue( head)
5. Do until no vertex left in a queue.

*/ 

void searchBFS()
 {
//this is how we define queue using LinkedList
  Queue<Character> queue=new LinkedList<Character>();
  
  queue.add(vertexlist[0].label);
  
  
 
  
  while(!queue.isEmpty())
  {
  
                 //element at head (Function in main graph class please use above link)
  ArrayList adjvertex=getNeighbours(queue.peek());
  System.out.println(queue.peek());
              //element removed at head
  queue.remove();
 
        if(adjvertex!=null)
  {
  for(int i=0;i<adjvertex.size();i++)
  {
               //element added at tail  
   queue.add((Character) adjvertex.get(i));
  }
  }
  }
  
  
 }

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