Write a public method that returns an int, with the signature:

findAlternativeDoor$($int$)$

where the parameter represents the number of the door that the contestant has selected. This method returns the number of the alternative door the contestant could choose as follows: if the door the contestant selected has a goat behind it$,$ this method should return the door number that holds the car. If the door selected by the contestant holds the car, the method should randomly return one of the other two door numbers.

There are many ways of writing this method, but you may find it useful to look at the documentation of the ArrayList class.