How do I find an element position in std::vector?

Question

I need to find an element position in an std::vector to use it for referencing an element in another vector:

int find( const vector& whe         


        

Answer 1

First of all, do you really need to store indices like this? Have you looked into std::map, enabling you to store key => value pairs?

Secondly, if you used iterators instead, you would be able to return std::vector.end() to indicate an invalid result. To convert an iterator to an index you simply use

size_t i = it - myvector.begin();