297. 二叉树的序列化与反序列化/C++

最新推荐文章于 2024-08-30 16:38:07 发布

原创最新推荐文章于 2024-08-30 16:38:07 发布 · 487 阅读

0 ·

CC 4.0 BY-SA版权

LeetCode/C++ 专栏收录该内容

248 篇文章

订阅专栏

本文介绍了一种二叉树的序列化和反序列化方法，使用队列遍历将二叉树转化为字符串，并能从字符串还原成原来的二叉树结构。通过具体的C++实现代码，展示了如何进行序列化和反序列化的操作。

在这里插入图片描述
不知道为什么在leetcode上会栈溢出，在vs上跑都是好的。
序列化：树→字符串数组→字符串
反序列化：字符串→字符串数组→树
字符串的格式为"1,2,3,#,#,4,5;"

/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
 * };
 */
class Codec {
public:

    // Encodes a tree to a single string.
    string serialize(TreeNode* root) {
        if(!root) return "";
        
        string str;
        vector<string> vec;
        queue<TreeNode*> que;
        que.push(root);
        while(!que.empty()){
            TreeNode* cur = que.front();
            que.pop();
            if(!cur){
                vec.push_back("#");
                continue;
            }else{
                vec.push_back(to_string(cur->val));
                que.push(cur->left);
                que.push(cur->right);
            }
        }
        
        while(vec.back()=="#")
            vec.pop_back();
        
        for(int i=0;i<vec.size();++i){
            if(i==vec.size()-1)
                str += vec[i] + ";";
            else
                str += vec[i] + ","; 
        }
        return str;
    }

    // Decodes your encoded data to tree.
    TreeNode* deserialize(string data) {
        if(data.empty()) return nullptr;
        
        int n = data.size();
        vector<string> vec;
        
        int i=0;
        while(i<n-1){
            string str;
            while(data[i]!=';' || data[i]!=',')
                str+=data[i++];
            vec.push_back(str);
            ++i;
        }
        
        int index = 0;
        int m = vec.size();
        TreeNode* root = new TreeNode(stoi(vec[index]));
        queue<TreeNode*> que;
        que.push(root);
        while(!que.empty()){
            TreeNode* cur = que.front();
            que.pop();
            if(!cur) continue;
            
            int leftIndex = 2*index+1;
            if(leftIndex<m && vec[leftIndex]!="#")
                cur->left = new TreeNode(stoi(vec[leftIndex]));
            else
                cur->left = nullptr;
            
            int rightIndex = leftIndex+1;
            if((leftIndex)<m && vec[leftIndex]!="#")
                cur->right = new TreeNode(stoi(vec[leftIndex]));
            else
                cur->right = nullptr;
            
            que.push(cur->left);
            que.push(cur->right);
            ++index;
        }
        return root;
    }
};

// Your Codec object will be instantiated and called as such:
// Codec codec;
// codec.deserialize(codec.serialize(root));