About Classes and Member functions

[sitha]

Hi All;
I have two classes;
first class,

class  A
{
//
Public:
void read_data1(fstream&);
void write_data1(fstream&);
};

A::read_data1(fstream & in)
{
//reading data "here i use vector to store data"
}

B::write_data(fstream& out)
{
//writing data
}

second class,

class  B
{
//
void get_result(fstream &);
void out_result(fstream &);
}

Now my problem is, I want use the first class member function into second class member function as following,

B::get_result(fstream & in)
{
//.......reading data(directly use class A member funtion here)
}

B::out_result(fstream & out)
{
//.......writing data (directly use class A member function here)
}

Please tell me how can I do this?

Thanks in advance!

Rgds,
Sitha