LeetCode(94) Binary Tree Inorder Traversal解题报告

Given a binary tree, return the inorder traversal of its nodes’ values.

For example:

Given binary tree {1,#,2,3},

1
\
2
/
3

return [1,3,2].

Note: Recursive solution is trivial, could you do it iteratively?

解题思路:

二叉树中序遍历

/**
* Definition for a binary tree node.
* public class TreeNode {
*     int val;
*     TreeNode left;
*     TreeNode right;
*     TreeNode(int x) { val = x; }
* }
*/
public class Solution {
public List<Integer> inorderTraversal(TreeNode root) {
List<Integer> res = new ArrayList<Integer>();
if(root != null){
res.addAll(inorderTraversal(root.left));
res.add(root.val);
res.addAll(inorderTraversal(root.right));
}
return res;
}
}