Shor's algorithm is not the only algorithm that seems to be better on
a quantum computer than any classical computer for a problem which is
considered to be useful. In 1994 L. K. Grover, also of Bell Labs,
devised an algorithm to find an item in an unsorted list of *N* items
in
.758 operations. No classical algorithm can guarantee
finding the item in less than *N* operations, and in the average case
it would take *N*/2 operations. (Grover)