Binary search with returned index in STL?

Question

I need a binary search function.

I couldn\'t find any function in the standard library that will return the index of the found item, and if it wasn\'t found,

Answer 1

I'm quite certain the standard library doesn't include anything to do precisely what you're asking for.

To get what you want, you'll probably want to start from std::lower_bound or std::upper_bound, and convert the iterator it returns into an index, then complement the index of the value wasn't found.