题解 | #二叉搜索树的第k个节点#

class Solution {

public:

TreeNode *res = NULL;
void midOrder(TreeNode *proot, int &k) {
    if(!proot || k < 0) return;
    midOrder(proot->left, k);
    k--;
    if(k == 0) {
        res = proot;
        res->left = NULL;
        res->right =NULL;
    }
    midOrder(proot->right, k);
}

TreeNode* KthNode(TreeNode* proot, int k) {
    // write code here
    midOrder(proot, k);
    return res;
}

};