  Quantum computing takes fully advantage of the superposition principle to
increase greatly (even exponentially) the speed of calculations, relative to
the classical approach. The Deutsch-Jozsa algorithm is the simplest quantum
algorithm illustrating this power. Unfortunately, the standard derivation
involves several ingenious steps which usually leave students feeling that they
could never have figured out the algorithm by themselves. We present here a
different formulation of the problem which allows students to derive the
algorithm using only basic knowledge of quantum mechanics and linear algebra.
