CODE EXAMPLE FOR JAVA

binary search tree

// Java program to demonstrate
// insert operation in binary
// search tree
class BinarySearchTree {
 
    /* Class containing left
       and right child of current node
     * and key value*/
    class Node {
        int key;
        Node left, right;
 
        public Node(int item)
        {
            key = item;
            left = right = null;
        }
    }
 
    // Root of BST
    Node root;
 
    // Constructor
    BinarySearchTree() { root = null; }
 
    BinarySearchTree(int value) { root = new Node(value); }
 
    // This method mainly calls insertRec()
    void insert(int key) { root = insertRec(root, key); }
 
    /* A recursive function to
       insert a new key in BST */
    Node insertRec(Node root, int key)
    {
 
        /* If the tree is empty,
           return a new node */
        if (root == null) {
            root = new Node(key);
            return root;
        }
 
        /* Otherwise, recur down the tree */
        else if (key < root.key)
            root.left = insertRec(root.left, key);
        else if (key > root.key)
            root.right = insertRec(root.right, key);
 
        /* return the (unchanged) node pointer */
        return root;
    }
 
    // This method mainly calls InorderRec()
    void inorder() { inorderRec(root); }
 
    // A utility function to
    // do inorder traversal of BST
    void inorderRec(Node root)
    {
        if (root != null) {
            inorderRec(root.left);
            System.out.println(root.key);
            inorderRec(root.right);
        }
    }
 
    // Driver Code
    public static void main(String[] args)
    {
        BinarySearchTree tree = new BinarySearchTree();
 
        /* Let us create following BST
              50
           /     
          30      70
         /      /  
       20   40  60   80 */
        tree.insert(50);
        tree.insert(30);
        tree.insert(20);
        tree.insert(40);
        tree.insert(70);
        tree.insert(60);
        tree.insert(80);
 
        // print inorder traversal of the BST
        tree.inorder();
    }
}
// This code is contributed by Ankur Narain Verma