[JAVA/LeetCode] Top 100 Liked Question: 94. Binary Tree Inorder Traversal

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
/**
 *
 * @author HEESOO
 *
 */
/**
 * 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 {
    List<Integer> list;
    public List<Integer> inorderTraversal(TreeNode root) {
        list=new ArrayList<>();
        inorder(root);
        
        return list;
    }
    
    public void inorder(TreeNode node){
        if(node!=null){
            inorder(node.left);
            list.add(node.val);
            inorder(node.right);
        }
    }
}