lc-297

/**
 * 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.
 * <p>
 * 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.
 * <p>
 * Clarification: The input/output format is the same as how LeetCode serializes
 * a binary tree. You do not necessarily need to follow this format, so please be
 * creative and come up with different approaches yourself.
 * <p>
 * <p>
 * Example 1:
 * <p>
 * <p>
 * Input: root = [1,2,3,null,null,4,5]
 * Output: [1,2,3,null,null,4,5]
 * <p>
 * <p>
 * Example 2:
 * <p>
 * <p>
 * Input: root = []
 * Output: []
 * <p>
 * <p>
 * <p>
 * Constraints:
 * <p>
 * <p>
 * The number of nodes in the tree is in the range [0, 10⁴].
 * -1000 <= Node.val <= 1000
 * <p>
 * Related Topics树 | 深度优先搜索 | 广度优先搜索 | 设计 | 字符串 | 二叉树
 * <p>
 * 👍 985, 👎 0
 */
//leetcode submit region begin(Prohibit modification and deletion)

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode(int x) { val = x; }
 * }
 */
public class Codec {
    public String serialize(TreeNode root) {
        return rserialize(root, "");
    }

    public TreeNode deserialize(String data) {
        String[] dataArray = data.split(",");
        List<String> dataList = new LinkedList<String>(Arrays.asList(dataArray));
        return rdeserialize(dataList);
    }

    public String rserialize(TreeNode root, String str) {
        if (root == null) {
            str += "null,";
        } else {
            str += str.valueOf(root.val) + ",";
            str = rserialize(root.left, str);
            str = rserialize(root.right, str);
        }
        return str;
    }

    public TreeNode rdeserialize(List<String> dataList) {
        if (dataList.get(0).equals("null")) {
            dataList.remove(0);
            return null;
        }
        TreeNode root = new TreeNode(Integer.valueOf(dataList.get(0)));
        dataList.remove(0);
        root.left = rdeserialize(dataList);
        root.right = rdeserialize(dataList);
        return root;
    }
}

// Your Codec object will be instantiated and called as such:
// Codec ser = new Codec();
// Codec deser = new Codec();
// TreeNode ans = deser.deserialize(ser.serialize(root));
//leetcode submit region end(Prohibit modification and deletion)