iterators

Hello.
In C++, I'm using an iterator to iterate through a vector of pointers.
How do I perform operations on the iterator?
I've tried several things but keep getting errors. This is where I get the error:

//In constructor of interface class
d_ClassA.push_back(new Class B(3)); //d_ClassA is a..                                     //std::vector<ClassA*>
...

//member-function in interface class
...
for (vector<ClassA*>::iterator i = 0; i != d_ClassA.end(); i++) {
    string classAFilename= (*i)->getFilename();
...

I guess there could be something else that is wrong. But is the code above correct?

>>3
In case you couldn't tell by looking, the error is 'Segmentation fault'.