package chapter4TreesAndGraphs;

public class BTree {

public Node root;

class Node {

int data;

Node left;

Node right;

public Node (int data, Node left, Node right){

this.data = data;

this.left = left;

this.right = right;

}

public Node(int data) {

this.data = data;

left = null;

right = null;

}

}

public static void main (String[] args) {

BTree bt = new BTree();

Node n5 = bt.new Node(8,null,null);

Node n6 = bt.new Node(9,null,null);

Node n3 = bt.new Node(6,null,null);

Node n4 = bt.new Node(7,null,null);

Node n1 = bt.new Node(4,n3,n4);

Node n2 = bt.new Node(5,n5,n6);

Node root = null;

bt.insertNode(root, 100);

System.out.println(root);

bt.insertNode(bt.root, 7);

bt.insertNode(bt.root,8);

System.out.println("Preorder:");

bt.preorder(bt.root);

System.out.println();

System.out.println("Inorder:");

bt.inorder(bt.root);

System.out.println();

System.out.println("Postorder:");

bt.postorder(bt.root);

}

public void preorder (Node node) {

if(node == null) return;

System.out.print(node.data + " ");

preorder(node.left);

preorder(node.right);

}

public void inorder (Node node) {

if(node == null) return;

inorder(node.left);

System.out.print(node.data + " ");

inorder(node.right);

}

public void postorder (Node node) {

if(node == null) return;

postorder(node.left);

postorder(node.right);

System.out.print(node.data + " ");

}

public void insertNode(Node root, int data){

if(root == null) root = new Node(data);

else if(data<=root.data) {

if(root.left==null) {

root.left = new Node(data);

}else

insertNode(root.left, data);}

else {

if(root.right==null) {

root.right = new Node(data);

}else

insertNode(root.right,data);

}

}

}