/* Six degrees of separation is the theory that everyone and everything is six or fewer steps away, by way of introduction, from any other person in the world, so that a chain of "a friend of a friend" statements can be made to connect any two people in a maximum of six steps.

Let's have a look at Hollywood actors. Two actors are related if they played in the same movie. Find the degree of separation for any two given actors in your database.


Example
- Angelina Jollie: Mr. and Mrs. Smith, Salt
- Brad Pitt: Mr. and Mrs. Smith, Haloween Joke
- Jake Jim: Haloween Joke
- Graham Bell: Electric Light

getMoviesForActor("Angelina Jolie"); // returns ["Mr. and Mrs. Smith", "Salt"]
getActorsInMovie("Mr. and Mrs. Smith"); // returns ["Angelina Jolie", "Brad Pitt"]

The degree of separation between "Angelina Jollie" and "Jake Jim" is 2 because the simplest connection between the two actors contains two relationships through movies "Mr. and Mrs. Smith" and "Haloween Joke".

The degree of separation between "Graham Bell" and "Jake Jim" is "-1" because they are not connected. -1 is simply a special value that represents there is no connection.

Assumptions:
- all actor names are unique
- all movie names are unique

You’re given the following API from your movie database (e.g., IMDB):

List<String> getMoviesForActor(String actorName)
List<String> getActorsInMovie(String movieName)

Implement the following method using the API's above:

int getDegreeOfSeperation(String actor1, String actor2);