question: public static int collectionContainsAll ( Collection < ? > c , Collection < ? > c2 ) { int mismatch = 0 ; for ( Object o : c2 ) { if ( ! c . contains ( o ) ) mismatch ++ ; } return mismatch > 0 ? - mismatch : c2 . size ( ) + 1 ; }
target:  Helper function that is called instead of Collection.containsAll