3.1. addSecond Implement the addSecond method in IntSinglyLinkedList. This method takes an Integer as an argument and adds it as the second element in the list. Here is an example of adding the Integer 7 to a list with two elements. Abstract view: addSecond(7) on the list [12, 100] turns the list into [12, 7, 100]

public void addSecond(Integer e) \{ \}