 Classical computers are bounded to the worst case of exactly formula_174 iterations when performing binary search.Quantum algorithms for binary search are still bounded to a proportion of formula_175 queries (representing iterations of the classical procedure), but the constant factor is less than one, providing for a lower time complexity on quantum computers.Any "exact" quantum binary search procedure—that is, a procedure that always yields the correct result—requires at least formula_176 queries in the worst case, where formula_177 is the natural logarithm.