Updated the exercise to use SIMD. This allows us to
cross-reference the concept from 112_vectors back to 005_arrays2,
introducing a handy feature of vectors early on.
See #430
When I hit 999 exercises, I will finally have reached the ultimate
state of soteriological release and no more exercises will be needed.
The cycle will be complete. All that will be left is perfect quietude,
freedom, and highest happiness.