algorithm Grover's algorithm
Grover's algorithm searches an unstructured database (or an unordered list) with N entries, for a marked entry, using only 



O
(


N


)


{\displaystyle O({\sqrt {N}})}

 queries instead of the 



O
(

N

)


{\displaystyle O({N})}

 queries required classically. Classically, 



O
(

N

)


{\displaystyle O({N})}

 queries are required even allowing bounded-error probabilistic algorithms.
