leetcode297. 二叉树的序列化与反序列化

代码

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode(int x) { val = x; }
 * }
 */
public class Codec {
// Encodes a tree to a single string.
    public String serialize(TreeNode root) {
        if (root == null) {
            return "#!";
        }
        String res = root.val + "!";
        res += serialize(root.left);
        res += serialize(root.right);
        return res;
    }

    // Decodes your encoded data to tree.
    public TreeNode deserialize(String preStr) {
        String[] values = preStr.split("!");
        Queue<String> queue = new LinkedList<>();
        for(int i = 0; i != values.length; i++){
            queue.offer(values[i]);
        }
        return deserialize(queue);
    }
    private TreeNode deserialize(Queue<String> queue){
        String value = queue.poll();
        if(value.equals("#")){
            return null;
        }
        TreeNode node = new TreeNode(Integer.valueOf(value));
        node.left = deserialize(queue);
        node.right = deserialize(queue);
        return node;
    }
}

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