Suppose we are implementing a binary tree as a linked structure of BinaryTreeNode objects. Write a method that will print out all of the nodes of tree via a preorder traversal. You may assume that the class has a reference to a BinaryTreeNode object called root. In addition, your method may take a reference to a BinaryTreeNode object as a parameter.

What will be an ideal response?

```
public void preorder(BinaryTreeNode root)
{
System.out.println(root.getElement());
if(root.getLeftChild() != null)
preorder(root.getLeftChild());
if(root.getRightChild() != null)
preorder(root.getRightChild());

}
```