Could please someone give a layman's explanation for this bombshell?<p>> Assume I hide a ball in a cabinet with a million drawers. How many drawers do you have to open to find the ball? Sometimes you may get lucky and find the ball in the first few drawers but at other times you have to inspect almost all of them. So on average it will take you 500,000 peeks to find the ball. <i>Now a quantum computer can perform such a search looking only into 1000 drawers.</i> This mind boggling feat is known as Grover’s algorithm.<p>If 999,000 drawers are left unopened, how can the algorithm guarantee that the ball will be found?