how does overloading of const and non-const functions work?

Question

The stl is full of definitions like this:

iterator begin ();
const_iterator begin () const;

As return value does not participate in overloa

Answer 1

Yes, the const modifier affects overloading. If myvector is const at that point const version will be called:

void stuff( const vector& myvector )
{
    vector::const_iterator it = myvector.begin(); //const version will be called
}

vector myvector;    
vector::const_iterator it = myvector.begin(); //non-const version will be called