depends how big n gets in the context of that particular function. a O(2^n) can be faster real world that O(1) if the overhead of the O(1) is bigger than the O(

depends how big n gets in the context of that particular function. a O(2^n) can be faster real world that O(1) if the overhead of the O(1) is bigger than the O(2^n) version. Its important to remmeber that big O is a measure of worst case as n grows. If N is bounded by the realities of the business case, it might not be so bad.