출처 : https://leetcode.com/problems/binary-tree-inorder-traversal/
Binary Tree Inorder Traversal - LeetCode
Can you solve this real interview question? Binary Tree Inorder Traversal - Given the root of a binary tree, return the inorder traversal of its nodes' values. Example 1: [https://assets.leetcode.com/uploads/2020/09/15/inorder_1.jpg] Input: root = [1,nu
leetcode.com
/**
* Definition for a binary tree node.
* public class TreeNode {
* int val;
* TreeNode left;
* TreeNode right;
* TreeNode() {}
* TreeNode(int val) { this.val = val; }
* TreeNode(int val, TreeNode left, TreeNode right) {
* this.val = val;
* this.left = left;
* this.right = right;
* }
* }
*/
class Solution {
public List<Integer> inorderTraversal(TreeNode root) {
List<Integer> list = new ArrayList<>();
if(root == null) return list;
InOrder(list, root);
return list;
}
private void InOrder(List<Integer> list, TreeNode root) {
if(root == null) return;
InOrder(list, root.left);
list.add(root.val);
InOrder(list, root.right);
}
}