Question

I’m trying to insert multiple times this same key into map but with different values. It doesn’t work. I know that operator[] does this job, but my question is, if this behaviour of insert is correct? Shouldn’t insert() inserts? I wonder what standard says. Unfortunately I don’t have it(Standard for C++) so I can’t check.
Thank you for helpful ansers.

Answer 1

If you want to insert the same key with different values, you need std::multimap instead.

The std::map::insert will not do anything if the key already exists.
The std::map::operator[] will overwrite the old value.

For STL reference you don`t necesary need the C++ standard itself; something like http://www.cplusplus.com/reference/ will do too.