題目

劍指 Offer 36. 二叉搜尋樹與雙向連結串列

我的思路

我的實現

/*
// Definition for a Node.
class Node {
public:
    int val;
    Node* left;
    Node* right;

    Node() {}

    Node(int _val) {
        val = _val;
        left = NULL;
        right = NULL;
    }

    Node(int _val, Node* _left, Node* _right) {
        val = _val;
        left = _left;
        right = _right;
    }
};
 
*/
class Solution {
    Node* preNode;
    Node *tailNode;
    Node *headNode;
    void visit(Node *root){
        //cout<<root->val<<endl;
        preNode->right = root;
        root->left = preNode;
        preNode = root;
    }
    void midSearch(Node *root){
        if(root!=NULL){
            
            
 
if(root!=tailNode||root!=headNode){
                midSearch(root->left);
                visit(root);
                if(root->right!=headNode)
                midSearch(root->right);
            }
            else{
                visit(root);
            }           
        }
    }
public
 
:
    Node* treeToDoublyList(Node* root) {
        tailNode = root;
        headNode = root;
        if(tailNode!=NULL){
            while(tailNode->right!=NULL)tailNode = tailNode->right;
            while(headNode->left!=NULL)headNode = headNode->left;
            preNode = tailNode;
            midSearch(root);

        }
        return headNode;



        
    }
};

拓展學習