leetcode_c++:树:Serialize and Deserialize Binary Tree（297）

Serialization is the process of converting a data structure or object into a sequence of bits so that it can be stored in a file or memory buffer, or transmitted across a network connection link to be reconstructed later in the same or another computer environment.

Design an algorithm to serialize and deserialize a binary tree. There is no restriction on how your serialization/deserialization algorithm should work. You just need to ensure that a binary tree can be serialized to a string and this string can be deserialized to the original tree structure.

For example, you may serialize the following tree

    1   / \  2   3     / \    4   5

as “[1,2,3,null,null,4,5]”, just the same as how LeetCode OJ serializes a binary tree. You do not necessarily need to follow this format, so please be creative and come up with different approaches yourself.

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算法

http://www.cnblogs.com/grandyang/p/4913869.html

// Recursionclass Codec {public:    // Encodes a tree to a single string.    string serialize(TreeNode* root) {        ostringstream out;        serialize(root, out);        return out.str();    }    // Decodes your encoded data to tree.    TreeNode* deserialize(string data) {        istringstream in(data);        return deserialize(in);    }private:    void serialize(TreeNode *root, ostringstream &out) {        if (root) {            out << root->val << ' ';            serialize(root->left, out);            serialize(root->right, out);        } else {            out << "# ";        }    }    TreeNode* deserialize(istringstream &in) {        string val;        in >> val;        if (val == "#") return nullptr;        TreeNode *root = new TreeNode(stoi(val));        root->left = deserialize(in);        root->right = deserialize(in);        return root;    }};