Java | Leetcode Java题解之第449题序列化和反序列化二叉搜索树

题目：

题解：

public class Codec {public String serialize(TreeNode root) {List<Integer> list = new ArrayList<Integer>();postOrder(root, list);String str = list.toString();return str.substring(1, str.length() - 1);}public TreeNode deserialize(String data) {if (data.isEmpty()) {return null;}String[] arr = data.split(", ");Deque<Integer> stack = new ArrayDeque<Integer>();int length = arr.length;for (int i = 0; i < length; i++) {stack.push(Integer.parseInt(arr[i]));}return construct(Integer.MIN_VALUE, Integer.MAX_VALUE, stack);}private void postOrder(TreeNode root, List<Integer> list) {if (root == null) {return;}postOrder(root.left, list);postOrder(root.right, list);list.add(root.val);}private TreeNode construct(int lower, int upper, Deque<Integer> stack) {if (stack.isEmpty() || stack.peek() < lower || stack.peek() > upper) {return null;}int val = stack.pop();TreeNode root = new TreeNode(val);root.right = construct(val, upper, stack);root.left = construct(lower, val, stack);return root;}
}