Question

For loop iterates through the vector and show all strings on the console successfully:

int main(int argc, const char * argv[])
{
    vector<string>stringVector;
    string newStringEntry;

    cin>>newStringEntry;
    stringVector.push_back(newStringEntry);

    cin>>newStringEntry;
    stringVector.push_back(newStringEntry);

    for (vector<string>::iterator i = stringVector.begin(); i != stringVector.end(); ++i) 
    {
        cout<<*i<<endl;
    }
}

But this makes the code hard to read (said our teacher) now we have to build a class for the for loop and the main should look like this after the change:

int main(int argc, const char * argv[])
{
    vector<string>stringVector;
    string newStringEntry;

    cin>>newStringEntry;
    stringVector.push_back(newStringEntry);

    cin>>newStringEntry;
    stringVector.push_back(newStringEntry);

    showStrings();
}

The problem I see is that I cannot just copy paste the for loop to an own class because
the vector name I declare in the main is not known in the class so I get an error.

How can I get this working?

My class so far looks like this:

class VectorHelp {
    void showStrings() const 
    {
        for (vector<string>::iterator i = vectorName.begin();
                i != vectorName.end();
                ++i)
        {
            cout << *i << endl;
        }
    }
};

Answer 1

You need to pass your vector<strings> as a method parameter:

VectorHelp::showStrings(stringVector);

...

static void showStrings(const vector<string>& stringVector)

Note that the name of your formal and actual parameter do not need to be the same. Also note that showStrings should be a class member function (i.e. static), not an instance member function.

Finally, note that printing without loops can be done using facilities of the standard C++ library:

ostream_iterator<string> out_it (cout, "\n");
copy (stringVector.begin(), stringVector.end(), out_it);