package com.cool.hot100.binary_tree; import java.util.ArrayList; import java.util.List; /** * Created with IntelliJ IDEA. * * @Author: Cool * @Date: 2024/08/28/23:02 * DayNumber 1 * Hard 1 * Level 3 */ public class Num94 { public List inorderTraversal(TreeNode root) { List list=new ArrayList<>(); mediumTraverse(root,list); return list; } private void mediumTraverse(TreeNode root,List list){ if(root==null){ return; } mediumTraverse(root.left,list); list.add(root.val); mediumTraverse(root.right,list); } }