Inorder Traversal and BST Java

PROGRAM TO FOR INORDER TREE TRAVERSAL WITHOUT RECURSION




import java.util.Stack;

 

/* Class containing left and right child of

current node and key value*/

class Node

{

    int data;

    Node left, right;

 

    public Node(int item)

    {

        data = item;

        left = right = null;

    }

}

 

/* Class to print the inorder traversal */

class BinaryTree

{

    Node root;

    void inorder()

    {

        if (root == null)

            return;

 

 

        Stack<Node> s = new Stack<Node>();

        Node curr = root;

 

        // traverse the tree

        while (curr != null || s.size() > 0)

        {

 

            /* Reach the left most Node of the

            curr Node */

            while (curr !=  null)

            {

                /* place pointer to a tree node on

                   the stack before traversing

                  the node's left subtree */

                s.push(curr);

                curr = curr.left;

            }

 

            /* Current must be NULL at this point */

            curr = s.pop();

 

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

 

            /* we have visited the node and its

               left subtree.  Now, it's right

               subtree's turn */

            curr = curr.right;

        }

    }

 

    public static void main(String args[])

    {

 

        /* creating a binary tree and entering

        the nodes */

        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.inorder();

    }

}




OUTPUT:

Minimum value in BST is 1

CREDITS: https://www.geeksforgeeks.org/find-the-minimum-element-in-a-binary-search-tree/