private void Helper(LeetCode173TreeNode root) { if (root == null) { return; } Helper(root.left); inorder.Enqueue(root.val); Helper(root.right); }
public LeetCode173(LeetCode173TreeNode root) { Helper(root); }
public LeetCode173TreeNode(int val = 0, LeetCode173TreeNode left = null, LeetCode173TreeNode right = null) { this.val = val; this.left = left; this.right = right; }