Live coding challenge test

Given a user id and a value k, return the top k friend suggestions for the user where a valid friend suggestion is a friend of a friend that isn't already your friend and "top" is defined by the number of mutual friends they have with you (e.g. if given the choice between a user who has 100 mutual friends with you versus one with only 2, the one with 100 mutual friends is likely the better friend suggestion)

Given the following graph of some friends:

graph LR
    1 --- 2
    1 --- 6
    1 --- 4
    2 --- 3
    2 --- 6
    3 --- 4
    4 --- 5

Using the function IFacebookClient.getFriends:

Given Id 1, returns [2, 4, 6]

Given Id 2, returns [1, 3, 5]

Given Id 3, returns [2, 4]

Given Id 4, returns [1, 3, 5]

Given Id 5, returns [4]

Given Id 6, returns [1, 2]

When calling FriendSuggester.getFriendSuggestions(1, 2), it should return [3, 5] because user 3 has 1 mutual friend with user 1 and user 5 has 1 mutual friend with user 1.