lintcode-85-在二叉查找树中插入节点

85-在二叉查找树中插入节点

给定一棵二叉查找树和一个新的树节点，将节点插入到树中。
你需要保证该树仍然是一棵二叉查找树。

注意事项

You can assume there is no duplicate values in this tree + node.

样例

给出如下一棵二叉查找树，在插入节点6之后这棵二叉查找树可以是这样的：

挑战

能否不使用递归？

标签

二叉查找树 LintCode 版权所有

code

/**
 * Definition of TreeNode:
 * class TreeNode {
 * public:
 *     int val;
 *     TreeNode *left, *right;
 *     TreeNode(int val) {
 *         this->val = val;
 *         this->left = this->right = NULL;
 *     }
 * }
 */
class Solution {
public:
    /**
     * @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.
     */
    TreeNode* insertNode(TreeNode* root, TreeNode* node) {
        // write your code here
        TreeNode* curNode = root, *curNodeNext = root;
        if(root == NULL) {
            root = node;
        }
        while(curNodeNext != NULL) {
            if(curNodeNext->val > node->val) {
                curNode = curNodeNext;
                curNodeNext = curNodeNext->left;
                if(curNode->left == NULL) {
                    curNode->left = node;
                    break;
                }
            }
            else if(curNodeNext->val < node->val) {
                curNode = curNodeNext;
                curNodeNext = curNodeNext->right;
                if(curNode->right == NULL) {
                    curNode->right = node;
                    break;
                }
            }
        }
        return root;
    }
};