CountLeafNodesBinaryTreeIterative

//Java implementation to find leaf count of a given Binary tree
 import java.util.*;                                                    //Level-order traversal
/* Class containing left and right child of current                     //Time Complexity : O(n)
 node and key value*/
class Node 
{
    int data;
    Node left, right;
  
    public Node(int item) 
    {
        data = item;
        left = right = null;
    }
}
  
public class BinaryTree 
{
    //Root of the Binary Tree
    Node root;
      
    /* Function to get the count of leaf nodes in a binary tree*/
    int getLeafCount() 
    {
        return getLeafCount(root);
    }
  
    int getLeafCount(Node node) 
    {
        if (node == null)
            return 0;
 
    // Initialize empty queue.
    Queue<Node> q = new LinkedList<Node>();
 
    // Do level order traversal starting from root
    int count = 0; // Initialize count of leaves
    q.add(node);
    while (!q.isEmpty())
    {
        Node temp = q.remove();
 
        if (temp.left != null)
            q.add(temp.left);
        if (temp.right != null)
            q.add(temp.right);
        if (temp.left == null && temp.right == null)
            count++;
    }
    return count;
    }
    
    /* Driver program to test above functions */
    public static void main(String args[]) 
    {
        /* create a tree */
        BinaryTree tree = new BinaryTree();
        tree.root = new Node(1);
        tree.root.left = new Node(2);
        tree.root.right = new Node(3);
        tree.root.left.left = new Node(4);
        tree.root.left.right = new Node(5);
          
        /* get leaf count of the abve tree */
        System.out.println("The leaf count of binary tree is : "
                             + tree.getLeafCount());
    }
}