public static string Tree2Str(LeetCode606TreeNode root)
{
if (root == null)
{
return(string.Empty);
}
if (root.IsLeafNode())
{
return(root.val + "");
}
if (!root.HasRightChild())
{
return($"{root.val}({Tree2Str(root.left)})");
}
// since this is the binary tree, so if it has right child it must have left child
return($"{root.val}({Tree2Str(root.left)})({Tree2Str(root.right)})");
}
public LeetCode606TreeNode(int val = 0, LeetCode606TreeNode left = null, LeetCode606TreeNode right = null)
{
this.val = val;
this.left = left;
this.right = right;
}