标签：dal val res cross ring instant should tree restrict
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 an N-ary tree. An N-ary tree is a rooted tree in which each node has no more than N children. There is no restriction on how your serialization/deserialization algorithm should work. You just need to ensure that an N-ary 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 3-ary tree
思路
1. preorder recursive traversal
2. add number of children after root val, in order to know when to terminate
1 3 3 2 5 0 6 0 2 0 4 0
代码
1 /* 2 // Definition for a Node. 3 class Node { 4 public int val; 5 public List<Node> children; 6 7 public Node() {} 8 9 public Node(int _val,List<Node> _children) { 10 val = _val; 11 children = _children; 12 } 13 }; 14 */ 15 class Codec { 16 // Encodes a tree to a single string. 17 public String serialize(Node root) { 18 List<String> list = new LinkedList<>(); 19 buildString(root, list); 20 return String.join(",", list); 21 } 22 23 private void buildString(Node root, List<String> list) { 24 if (root == null) return; 25 26 list.add(String.valueOf(root.val)); 27 list.add(String.valueOf(root.children.size())); 28 for (Node child : root.children) { 29 buildString(child, list); 30 } 31 32 } 33 34 // Decodes your encoded data to tree. 35 public Node deserialize(String data) { 36 if (data.length() == 0) return null; 37 String[] strArr = data.split(","); 38 Queue<String> queue = new LinkedList<>(); 39 Collections.addAll(queue, strArr); 40 return buildTree(queue); 41 } 42 43 private Node buildTree(Queue<String> queue) { 44 // match the given constructor form 45 Node root = new Node(); 46 root.val = Integer.parseInt(queue.poll()); 47 int size = Integer.parseInt(queue.poll()); 48 root.children = new ArrayList<>(size); 49 for (int i = 0; i < size; i++) { 50 root.children.add(buildTree(queue)); 51 } 52 return root; 53 } 54 } 55 56 57 // Your Codec object will be instantiated and called as such: 58 // Codec codec = new Codec(); 59 // codec.deserialize(codec.serialize(root));
[leetcode]428. Serialize and Deserialize N-ary Tree序列化与反序列化N叉树
标签：dal val res cross ring instant should tree restrict
原文地址：https://www.cnblogs.com/liuliu5151/p/9897169.html
