i am using upperbound and lowerbound in c++ regularly but i don't know actual algorithm behind this??? Plzz help..
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i am using upperbound and lowerbound in c++ regularly but i don't know actual algorithm behind this??? Plzz help..
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It's a simple binary search.
http://www.cplusplus.com/reference/algorithm/upper_bound/
Actually i m not able to understand this step. std::advance (it,step);
bcoz this step is linear and this will increase it's complexity..?
its just equal to it+step in our case, works for O(1)
It's O ( 1 ) when you have random access iterators, on non random access iterators it has linear complexity.
http://www.cplusplus.com/reference/algorithm/lower_bound/