create class with array

I need to create an array of classes inside an other class.

Here you go:

class Class {};

class OtherClass {
    Class array[1];
};

you should look at using std::vector, instead of carring about C-style arrays.

This is more the C++ way of coding, imagine a class containing an array of double:

class A
{
public:
    std::vector<double> m_doubles;
}

EDIT: so for an array of class, let's say class B:

class A
{
public:
    std::vector<B> m_bs;
}

EDIT2:

and like @cppanda suggests in the comments below, the implementation of std::vector is done in the Standard C++ Library (also known as the STL). It's really worth the effort learning to use it intensively, a lot of things already done for you. ( like vector and many sorts of containers)

Have you created a class and arrays before? Here is some info. If you want to know something about arrays: here