235. Lowest Common Ancestor of a Binary Search Tree.cpp

/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
 * };
 */
​
class Solution {
public:
    TreeNode* lowestCommonAncestor(TreeNode* root, TreeNode* p, TreeNode* q) {
        if (root->val>p->val &root->val>q->val)
        {
            return lowestCommonAncestor(root->left,p,q);
        }
        else if (root->val<p->val & root->val<q->val)
        {
            return lowestCommonAncestor(root->right,p,q);
        }
        else { return root;}
    }
};