some containers in stl don't have find function

Question

Some of the STL containers such as std::list and std::vector don't have find() method as a member function. Why is that? I know that there is the alternative of using std::find from <algorithm> but still this use isn't 100% natural.

Answer 1

The general design principle is to use std::find where possible, and implement find member functions when it is more efficient.

The containers that do have a find member are containers which have a more efficient element look-up mechanism then the linear search performed in std::find. For example, binary search trees such as std::set and std::map, or hash tables such as their unordered counterparts.