Class AVL_Tree

Data Structures/Tree/Java/AVL_Tree.java:3–161

import java.util.*;

public class AVL_Tree {

    private Node root;

    private class Node {
        int data;
        Node left;
        Node right;
        int height;

        public Node(int data) {
            this.data = data;
            this.height = 1;
            left = null;
            right = null;
        }
    }

    // Inserting node in a tree
    public void insert(int num) {
        this.root = insert(this.root, num);
    }

    // Inorder Traversal
    public void inOrder(Node node) {
        if (node != null) {
            inOrder(node.left);
            System.out.print(node.data + " ");
            inOrder(node.right);
        }
    }

    // Preorder traversal
    public void preOrder(Node node) {
        if (node != null) {
            System.out.print(node.data + " ");
            preOrder(node.left);
            preOrder(node.right);
        }
    }

    // Postorder traversal
    public void postOrder(Node node) {
        if (node != null) {
            postOrder(node.left);
            postOrder(node.right);
            System.out.print(node.data + " ");
        }
    }

    private Node insert(Node node, int num) {

        if (node == null) {
            Node node_new = new Node(num);
            return node_new;
        }

        if (num > node.data) {