297. Serialize and Deserialize Binary Tree

focusj 发布于2019-08-14 14:15 / 1938人阅读

摘要：题目解答用一个特殊的符号来表示的情况这是按先序遍历来存到中去这里用为其包含了几乎所有这里还是挺多知识点的，后是一个可以把数组变成则是把加到这个的中去

题目：
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

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.
Note: Do not use class member/global/static variables to store states. Your serialize and deserialize algorithms should be stateless.

解答：

public class Codec {
    private String spliter = ",";
    //用一个特殊的符号来表示null的情况
    private String NN = "X";

    // Encodes a tree to a single string.
    public void BuildString(StringBuilder sb, TreeNode root) {
        if (root == null) {
            sb.append("X").append(spliter);
        } else {
            //这是按先序遍历来存root到string中去
            sb.append(root.val).append(spliter);
            BuildString(sb, root.left);
            BuildString(sb, root.right);
        }
    }
    
    public String serialize(TreeNode root) {
        StringBuilder sb = new StringBuilder();
        BuildString(sb, root);
        return sb.toString();
    }

    // Decodes your encoded data to tree.
    public TreeNode BuildTree(Deque nodes) {
        String node = nodes.remove();
        if (node.equals(NN)) {
            return null;
        } else {
            //Integer.valueOf("String");
            TreeNode root = new TreeNode(Integer.valueOf(node));
            root.left = BuildTree(nodes);
            root.right = BuildTree(nodes);
            return root;
        }
    }
    
    public TreeNode deserialize(String data) {
        //deque这里用linkedlist为interface,其包含了几乎所有resizable array
        Deque nodes = new LinkedList<>();
        //这里还是挺多知识点的，String.split()后是一个String[], Arrays.asList()可以把数组变成list, nodes.addAll()则是把list加到nodes这个list的中去
        nodes.addAll(Arrays.asList(data.split(spliter)));
        return BuildTree(nodes);
    }
}

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

私有云海外云主机 binary-tree binary-search-tree Deserialize serialize

文章版权归作者所有，未经允许请勿转载,若此文章存在违规行为，您可以联系管理员删除。

转载请注明本文地址：https://www.ucloud.cn/yun/64906.html

[LeetCode] 297. Serialize and Deserialize Binary T

Problem 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 li...

MRZYD 2019-08-19 11:13 评论0 收藏0
leetcode297. Serialize and Deserialize Binary Tree

摘要：因此题目中的例子的中序遍历结果为。但是，标准的中序遍历并不能使我们将该结果反构造成一棵树，我们丢失了父节点和子节点之间的关系。这里我们也可以明显的看出来，中序遍历需要保存的空值远远多于广度优先遍历。题目要求 Serialization is the process of converting a data structure or object into a sequence of ...

desdik 2019-08-15 14:30 评论0 收藏0
LeetCode 297. Serialize and Deserialize Binary Tre

摘要：题目大意将二叉树序列化，返回序列化的，和反序列化还原。解题思路技巧在于将记录为便于将来判断。的思想将每一层记录下来，反序列化时也按照层级遍历的方法依次设置为上一个里面的元素的左孩子和右孩子。变种，可以要求输出一个，而不是 LeetCode 297. Serialize and Deserialize Binary Tree 题目大意: 将二叉树序列化，返回序列化的String，和反序列...

cc17 2019-08-16 13:28 评论0 收藏0
Serialize and Deserialize Binary Tree & BST

摘要：思路理论上说所有遍历的方法都可以。但是为了使和的过程都尽量最简单，是不错的选择。用作为分隔符，来表示。复杂度代码思路这道题和之前不同，一般的树变成了，而且要求是。还是可以用，还是需要分隔符，但是就不需要保存了。 297. Serialize and Deserialize Binary Tree Serialization is the process of converting a...

eccozhou 2019-08-14 17:11 评论0 收藏0
[LintCode/LeetCode] Binary Tree Serialization

摘要：这里要注意的是的用法。所以记住，用可以从自动分离出数组。跳过第一个元素并放入数组最快捷语句建立的用意记录处理过的结点并按处理所有结点和自己的连接下面先通过判断，再修改的符号的顺序，十分巧妙更轻便的解法 Problem Design an algorithm and write code to serialize and deserialize a binary tree. Writin...

keithyau 2019-08-14 15:12 评论0 收藏0