Lintcode-easy-insert Node in a Binary Search Tree

Given a binary search tree and a new tree node, insert the node into the tree. You should keep the tree still is a valid binary search tree.

Example

Given binary search tree as follow, after Insert node 6, the tree should is:

  2             2 / \           / 1   4   -->   1   4   /             / \   3             3   6

Challenge

Can do it without recursion?

Both of these methods are written, recursive and non-recursive

1. Recursion

/*** Definition of TreeNode: * public class TreeNode {* public int val; * Public TreeNode left, right; * PU Blic TreeNode (int val) {* This.val = val; * This.left = This.right = null; *} *}*/ Public classSolution {/**     * @paramroot:the root of the binary search tree. * @paramNode:insert This node into the binary search tree *@return: The root of the new binary search tree. */     PublicTreeNode Insertnode (TreeNode root, TreeNode node) {//Write your code here        if(Root = =NULL)            returnnode; if(Root.val = =node.val) {            returnRoot; }                if(Root.left = =NULL&& root.val >node.val) {Root.left=node; returnRoot; }                if(Root.right = =NULL&& Root.val <node.val) {Root.right=node; returnRoot; }                if(Root.val >node.val) {TreeNode Left=Insertnode (root.left, node); Root.left=Left ; }        Else if(Root.val <node.val) {TreeNode Right=Insertnode (root.right, node); Root.right=Right ; }                returnRoot; }}

2. Non-recursive

/*** Definition of TreeNode: * public class TreeNode {* public int val; * Public TreeNode left, right; * PU Blic TreeNode (int val) {* This.val = val; * This.left = This.right = null; *} *}*/ Public classSolution {/**     * @paramroot:the root of the binary search tree. * @paramNode:insert This node into the binary search tree *@return: The root of the new binary search tree. */     PublicTreeNode Insertnode (TreeNode root, TreeNode node) {//Write your code here        if(Root = =NULL)            returnnode; if(Root.val = =node.val)returnRoot; TreeNode P=Root;  while(! (P.left = =NULL&& p.val > Node.val) &&! (P.right = =NULL&& P.val <node.val)) {            if(P.val >node.val) P=P.left; Else if(P.val = =node.val)returnRoot; ElseP=P.right; }        if(P.left = =NULL&& p.val >node.val) {P.left=node; returnRoot; }        Else{p.right=node; returnRoot; }    }}

Lintcode-easy-insert Node in a Binary Search Tree