Given a binary search tree and a new tree node, insert the node into the tree. You should keep the tree still be a valid binary search tree.
Have you met this question in a real interview? Yes
Example
Given binary search tree as follow, after Insert node 6, the tree should be:
2 2
/ \ / \
1 4 –> 1 4
/ / \
3 3 6
/**
* Definition of TreeNode:
* public class TreeNode {
* public int val;
* public TreeNode left, right;
* public TreeNode(int val) {
* this.val = val;
* this.left = this.right = null;
* }
* }
*/
public class Solution {
/**
* @param root: The root of the binary search tree.
* @param node: insert this node into the binary search tree
* @return: The root of the new binary search tree.
*/
public TreeNode insertNode(TreeNode root, TreeNode node) {
if (root == null) {
return node;
}
if (root.val > node.val) {
root.left = insertNode(root.left, node);
} else {
root.right = insertNode(root.right, node);
}
return root;
}
}