###### tags: `LeetCode` `Recursion` `Tree` `Medium`
# LeetCode #701 [Insert into a Binary Search Tree](https://leetcode.com/problems/insert-into-a-binary-search-tree/)
### (Medium)

/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode() : val(0), left(nullptr), right(nullptr) {}
 *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
 *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
 * };
 */
class Solution {
public:
    TreeNode* insertIntoBST(TreeNode* root, int val) {
        if(!root)return new TreeNode(val);
        insert(root, val);
        return root;
    }
    TreeNode* insert(TreeNode* node, int val){
        if(!node)return new TreeNode(val);
        if(node->val>val)node->left=insert(node->left, val);
        else if(node->val<val)node->right=insert(node->right, val);
        return node;
    }
};