1. 2 pts -- 1.5 pts for accumulator function
                    (preferably, but not necessarily hidden in a local)
             .5 pts for non-accumulator interface

2. 2 pts -- 1.5 pts for accumulator function
                    (preferably, but not necessarily hidden in a local)
             .5 pts for non-accumulator interface

3. 2 pts -- 1 pt for hand-evaluations
            1 pt for explanation
                     (The standard accumulator-based filter will build the
                      result in reverse order.  Acceptable to use when you
                      don't care about order, e.g., in quicksort.)

4. 2 pts -- 1.5 pts for main function
                    should use two accumulators
                    (preferably, but not necessarily hidden in a local)
             .5 pts for non-accumulator interface

5. 2 pts -- 1.5 pts for main function
                    should use accumulator
                    (preferably, but not necessarily hidden in a local)
             .5 pts for non-accumulator interface