LeetCode 297. 二叉树的序列化与反序列化

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/**
 * 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:
    void myserialize(TreeNode* root, string& data)
    {
        if(root == nullptr)
        {
            data+="None,";
            return;
        }
            
        data += to_string(root->val) + ",";
        myserialize(root->left, data);
        myserialize(root->right, data);
    }
    // Encodes a tree to a single string.
    string serialize(TreeNode* root) {
        string data = "";
        myserialize(root, data);
        return data;
    }

    TreeNode* mydeserialize(queue<string>& nodes)
    {
        if(nodes.front() == "None")
        {
            nodes.pop();
            return nullptr;
        }

        TreeNode* root = new TreeNode(stoi(nodes.front()));
        nodes.pop();
        root->left = mydeserialize(nodes);
        root->right = mydeserialize(nodes);

        return root;
    }

    // Decodes your encoded data to tree.
    TreeNode* deserialize(string data) {
        queue<string> nodes;

        string str = "";
        for(char& c : data)
        {
            if(c == ',')
            {
                nodes.push(str);
                str = "";
            }
            else
            {
                str += c;
            }
        }

        return mydeserialize(nodes);
    }
};

// Your Codec object will be instantiated and called as such:
// Codec ser, deser;
// TreeNode* ans = deser.deserialize(ser.serialize(root));