code: public static <E, C extends Comparator<E>> E maximum(Iterator<E> iterator, C comparator, E init) {
          return Reductions.reduce(iterator, BinaryOperator.maxBy(comparator), init);
      }
docs: Returns the max element contained in the iterator
  
  @param <E> the iterator element type parameter
  @param <C> the comparator type parameter
  @param iterator the iterator to be consumed
  @param comparator the comparator to be used to evaluate the max element
  @param init the initial value to be used
  @return the max element contained in the iterator