标签：stat sub use ensure node bst efi ted connect
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
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.
Note: Do not use class member/global/static variables to store states. Your serialize and deserialize algorithms should be stateless.
链接： http://leetcode.com/problems/serialize-and-deserialize-binary-tree/
5/14/2017
算法班，deserialize部分抄的
层序遍历的方法
注意
1. 第36行需要减去最后一个","
2. 第44行将string里面的各个char转为数字和#
3. deserialize部分，TreeNode部分来自于queue，新建的子树node值来自于values
1 /** 2 * Definition for a binary tree node. 3 * public class TreeNode { 4 * int val; 5 * TreeNode left; 6 * TreeNode right; 7 * TreeNode(int x) { val = x; } 8 * } 9 */ 10 public class Codec { 11 private final String nullNode = "#"; 12 private final String delimiter = ","; 13 14 // Encodes a tree to a single string. 15 public String serialize(TreeNode root) { 16 StringBuilder sb = new StringBuilder(); 17 if (root == null) return "#"; 18 19 Queue<TreeNode> queue = new LinkedList<TreeNode>(); 20 sb.append("["); 21 queue.offer(root); 22 while (!queue.isEmpty()) { 23 int size = queue.size(); 24 for (int i = 0; i < size; i++) { 25 TreeNode node = queue.poll(); 26 if (node == null) { 27 sb.append(nullNode); 28 } else { 29 sb.append(node.val); 30 queue.offer(node.left); 31 queue.offer(node.right); 32 } 33 sb.append(delimiter); 34 } 35 } 36 sb.deleteCharAt(sb.length() - 1); 37 sb.append("]"); 38 return sb.toString(); 39 } 40 41 // Decodes your encoded data to tree. 42 public TreeNode deserialize(String data) { 43 if (data.equals("#")) return null; 44 String[] values = data.substring(1, data.length() - 1).split(delimiter); 45 Queue<TreeNode> queue = new LinkedList<TreeNode>(); 46 TreeNode root = new TreeNode(Integer.parseInt(values[0])); 47 48 queue.offer(root); 49 for (int i = 1; i < values.length; i++) { 50 // node comes from queue, left/right comes from values 51 TreeNode parent = queue.poll(); 52 if (!values[i].equals(nullNode)) { 53 TreeNode left = new TreeNode(Integer.parseInt(values[i])); 54 parent.left = left; 55 queue.add(left); 56 } 57 i++; 58 if (!values[i].equals(nullNode)) { 59 TreeNode right = new TreeNode(Integer.parseInt(values[i])); 60 parent.right = right; 61 queue.add(right); 62 } 63 } 64 return root; 65 } 66 } 67 68 // Your Codec object will be instantiated and called as such: 69 // Codec codec = new Codec(); 70 // codec.deserialize(codec.serialize(root));
也可以递归调用
http://www.cnblogs.com/yrbbest/p/5047035.html
别人的答案
https://discuss.leetcode.com/topic/30195/recursive-dfs-iterative-dfs-and-bfs
更多讨论
https://discuss.leetcode.com/category/375/serialize-and-deserialize-binary-tree
297. Serialize and Deserialize Binary Tree
标签：stat sub use ensure node bst efi ted connect
原文地址：http://www.cnblogs.com/panini/p/6854567.html
