序列化和反序列化二叉树-蒲公英云

序列化和反序列化二叉树

小灰灰 2022-05-24 08:54 358阅读 0赞

这里写图片描述

import java.util.*;
 class TreeNode { 
    int val = 0;
    TreeNode left = null;
    TreeNode right = null;
    public TreeNode(int val) {
        this.val = val;
    }
}
public class Solution { 
      int index=-1;
    //序列化，将对象转换成字符串
   String Serialize(TreeNode root) {
        StringBuilder sb=new StringBuilder();
        if(root==null){
            sb.append("#,");
            return sb.toString();
        }
        sb.append(root.val+",");
        sb.append(Serialize(root.left));
        sb.append(Serialize(root.right));
        return sb.toString();
   }
   //反序列化
   TreeNode Deserialize(String str) {
        index++;
        String[]arr=str.split(",");
        TreeNode node=null;
        if(!arr[index].equals("#")){
             node=new TreeNode(Integer.valueOf(arr[index]));
             node.left=Deserialize(str);
             node.right=Deserialize(str);
        }
        return node;
  }
   //二叉树的层序遍历
    public String TreeBFS(TreeNode pRoot,String str)
    {
     Queue<TreeNode> arr=new LinkedList<TreeNode>();//存放元素的队列
     arr.offer(pRoot);
     boolean flag=false;
     while(!arr.isEmpty())
     {
           TreeNode temp=arr.poll();
          // System.out.println(temp.val);
           str+=temp.val;
            if(temp.left!=null)
            {
               arr.offer(temp.left);
            }
            if(temp.right!=null)
            {
               arr.offer(temp.right);
            }
     }
     System.out.println(str);
      return str;
    }
    public static void main(String[]args){
         //System.out.println("Hello");
        TreeNode root=new TreeNode(1);
        root.left=new TreeNode(2);
        root.right=new TreeNode(3);
        root.left.left=new TreeNode(4);
        root.left.right=new TreeNode(5);
        root.right.left=new TreeNode(6);
        root.right.right=new TreeNode(7);
        Solution s=new Solution();
        String str="";
        s.TreeBFS(root,str);
    }
}