搜索二叉搜索树

TreeNode* searchBST(TreeNode* root, int val) {
        if (root == NULL || root->val == val) return root;
        TreeNode* result = NULL;
        if (root->val > val) result = searchBST(root->left, val);
        if (root->val < val) result = searchBST(root->right, val);
        return result;
    }