1)Write a method delete() that takes an int argument k and deletes the kth element in a
linked list, if it exists.
(i want to be able to choose what my input k will be, i do want hard coded and do not use  )

2)Write a method max() that takes a reference to the first node in a linked list as argument and returns the value of the maximum key in the list. Assume that all keys are positive integers,and return 0 if the list is empty