Algorithm for Level Order Tree Traversals : Iterative Model(Non-Recursive way)

import java.util.LinkedList; import java.util.Queue; //Level Order Tree Traversals : Iterative Model(Non-Recursive way) class BinaryTreeLevelOrderTraversalIterativeModel {       class TreeNode {             TreeNode left, right;             int data; // considering integer data.                    public TreeNode(int dataItem) {                   this.data = dataItem;                   left = null;                   right = null;             }       }               TreeNode root;        BinaryTreeLevelOrderTraversalIterativeModel() {              root = null;        }               void printLevelOrderTraversal(TreeNode treeNode) {              if(treeNode == null)                     return;                           //Level0, Level1, Level2...              Queue<TreeNode> q = new LinkedList<TreeNode>();              q.offer(root);              while(!q.isEmpty()) {                     TreeNode temp = q.poll();                     System.out.println(temp.data);                                         if(temp.left != null) {                           q.offer(temp.left);                     }                                         if(temp.right != null) {                           q.offer(temp.right);                     }              }        }               void printLevelOrder() {              printLevelOrderTraversal(root);        }        public static void main(String[] args) {              BinaryTreeLevelOrderTraversalIterativeModel tree = new BinaryTreeLevelOrderTraversalIterativeModel();              tree.root = new TreeNode(1);                      tree.root.left = new TreeNode(2);              tree.root.right = new TreeNode(3);                      tree.root.left.left = new TreeNode(4);              tree.root.left.right = new TreeNode(5);                      tree.root.right.left = new TreeNode(6);              tree.root.right.right = new TreeNode(7);                      tree.printLevelOrder();        } } //Time Complexity: O(n). Space Complexity: O(n).

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