62 lines
1.6 KiB
Java
62 lines
1.6 KiB
Java
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import java.util.Queue;
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import java.util.LinkedList;
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/* Class to represent Tree node */
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class Node {
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int data;
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Node left, right;
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public Node(int item) {
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data = item;
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left = null;
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right = null;
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}
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}
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/* Class to print Level Order Traversal */
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class BinaryTree {
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Node root;
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/* Given a binary tree. Print its nodes in level order
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using array for implementing queue */
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void printLevelOrder()
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{
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Queue<Node> queue = new LinkedList<Node>();
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queue.add(root);
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while (!queue.isEmpty())
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{
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/* poll() removes the present head.
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For more information on poll() visit
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http://www.tutorialspoint.com/java/util/linkedlist_poll.htm */
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Node tempNode = queue.poll();
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System.out.print(tempNode.data + " ");
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/*Enqueue left child */
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if (tempNode.left != null) {
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queue.add(tempNode.left);
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}
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/*Enqueue right child */
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if (tempNode.right != null) {
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queue.add(tempNode.right);
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}
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}
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}
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public static void main(String args[])
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{
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/* creating a binary tree and entering
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the nodes */
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BinaryTree tree_level = new BinaryTree();
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tree_level.root = new Node(1);
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tree_level.root.left = new Node(2);
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tree_level.root.right = new Node(3);
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tree_level.root.left.left = new Node(4);
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tree_level.root.left.right = new Node(5);
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System.out.println("Level order traversal of binary tree is - ");
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tree_level.printLevelOrder();
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}
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}
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