Suppose we have a LinkedBinaryTree object named tree which stores only non$-$duplicated strings as elements. In the class LinkedBinaryTree, you need to provide a method named preorderNextElement$($String s$)$ such that the element s is present in a node that we call p$.$ This method should return the element of the node which is visited after p during a preorder traversal of the tree object $($or null if p is the last node visited$).$ Test this method in the main method of LinkedBinaryTree.

Hint: First, you may use a preorder traversal to collect the positions of the tree. Next, print the element of the position visited after p$.$