CommonFriendsFinder This is a MapReduce application, which finds a common friends between two friends. Input: A->B C D B->A C D E C->A B D E D->A B C E E->B C D Output: A B > C D A C > B D A D > B C B C > A D E B D > A C E B E > C D C D > A B E C E > B D D E > B C