Problem 1: Write a class that implements a generic binary search tree including the methods add, contains and printInorder. (We will do this as a group) Problem 2: Add a toString method to the class. This method returns a string of the form [e1, e2, , en] containing all of the elements in the tree in order. Problem 3: Add a method to the class that returns the number of leaves in the tree. Problem 4: Add a clone method to the class that returns a copy of the tree. Remember that we have three different ways of traversing a tree: preorder, inorder and postorder. Does it matter which one you use in this method? Problem 5: Add an equals method to the class. Two trees are equal if they include the same elements. The structure of the trees does not have to be the same.