BFS of a Binary Tree ( Level Order Traversal)

Problem Statement: 
    Traverse the Binary Tree Level by Level.

Solution :

There are two approches for BFS (Breadth First Search ) of a Binary Tree.
1. Using Queue
2. Recursive Approach.

In this post i will be solving the above problem with the recursive approach.

I have already posted the code for printing the nodes at a given level. So the only thing that we need to do for BFS of a tree is to calculate height of the tree and print nodes of the tree for each level.

Pls refer to the link for the working code.
Source Code

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/** * for printing BFS (recursive) * @param root */ public void printTreeBFS(Node root) { if(root==null) System.out.println("Empty Tree"); int height=height(root); for(int i=1 ; i<=height ; i++){ printLevel(root, i); System.out.println(); } } /** * Prints nodes at a given level * @param root * @param level */ public void printLevel(Node root, int level) { if(root==null) return ; if(level==1) System.out.print(root.data + "\t"); printLevel(root.left, level-1) ; printLevel(root.right, level-1) ; }