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Tree Traversals Program in java ( Preorder | PostOrder | InrderOrder )


                      Tree Traverseral ( PreOrder | PostOrder| InOrder )

class Node{
int key;
Node left,right;
public Node(int value){
key = value;
left = right = null;

public class BinaryTree {
Node root;
BinaryTree(int value){
root = new Node(value);
BinaryTree() {
root = null;

public void printInorder(Node node){
if(node == null)
return ;
System.out.print(node.key+ " ");
   void printInorder() {
   System.out.println("Inorder Traversal");

   void printPreOrder(Node node){
   if(node == null)
   System.out.print(node.key+" ");
   void printPreOrder(){
   System.out.println("Pre-order Traversal");
   void printPostOrder(Node node){
   if(node == null)
   System.out.print(node.key+" ");
   void printPostOrder(){
   System.out.println("Pre-order Traversal");
public static void main(String []args){
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);
tree.root.right.left= new Node(6);
tree.root.right.right = new Node(7);



Inorder Traversal
4 2 5 1 6 3 7 Pre-order Traversal
1 2 4 5 3 6 7 Pre-order Traversal
2 4 5 3 6 7 1 

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