序列化二叉树

题目

请实现两个函数，分别用来序列化和反序列化二叉树

思路

前序遍历（中左右），递归

/*public class TreeNode {    int val = 0;    TreeNode left = null;    TreeNode right = null;    public TreeNode(int val) {        this.val = val;    }}*/public class Solution {    int index = -1;    String Serialize(TreeNode root) {        String s = "";        if(root==null)            return "#,";        s += root.val+",";        s += Serialize(root.left);        s += Serialize(root.right);        return s;  }    TreeNode Deserialize(String str) {       index++;       String[] sstr = str.split(",");        if(index>=sstr.length)            return null;        TreeNode node = null;        while(!sstr[index].equals("#")){            node = new TreeNode(new Integer(sstr[index]));            node.left = Deserialize(str);            node.right = Deserialize(str);        }        return node;  }}