leetcode:235. Lowest Common Ancestor of a Binary Search Tree

个人学习笔记：在二叉搜索树中寻找最低共同父节点

很简单的题目，直接贴代码

/** * 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 == NULL){            return root;           }                int min = p->val > q->val ? q->val : p->val;        int max = p->val > q->val ? p->val : q->val;                if (root->val >= min && root->val <= max) {            return root;        }                if (root->val < min) {            return lowestCommonAncestor(root->right, p, q);        }                if (root->val > max) {            return lowestCommonAncestor(root->left, p, q);        }    }};