Tree_demo(Binary)

package pracss;

class Node{
	int key;
	int data;
	Node left , right;
	
	public Node (int item) {
		data = item;
		left = right = null;
	}
}
public class Binary_tree {
	//root of binary tree
	Node root;
	
	Binary_tree() {
		root = null;
	}
	void printPostorder(Node node) {
		if(node == null) 
			return;
			//first recur on left subtree
			printPostorder(node.left);
			
			printPostorder(node.right);
			
			System.out.print(node.data+ " " );	
	}
	
	void printInorder(Node node) {
		if(node == null) 
			return;
			//first recur on left subtree
			printInorder(node.left);
			
			System.out.print(node.data+ " " );
			
			printInorder(node.right);		
	}
	void printPreorder(Node node) {
		if(node == null) 
			return;
			//first recur on left subtree
			System.out.print(node.data+ " " );
		
			printPreorder(node.left);
			
			printPreorder(node.right);	
	}
	
	public static void main(String args[]) {
		Binary_tree tree = new Binary_tree();
		tree.root = new Node(40); // root node always 1
		tree.root.left = new Node(30);
		tree.root.right = new Node(50);
		tree.root.left.left = new Node(20);
		tree.root.left.right = new Node(35);
		tree.root.left.left.left = new Node(15);
		tree.root.left.left.right = new Node(25);
		
		System.out.println("Inorder traversal of binary treee is :");
		tree.printInorder(tree.root);
		System.out.println();
		System.out.println("Postorder traversal of binary treee is :");
		tree.printPostorder(tree.root);
		System.out.println();
		System.out.println("Preorder traversal of binary treee is :");
		tree.printPreorder(tree.root);
	}
}