acessing multi variables declared and initialised in one class from a different class

Im trying to code a program with multiple classes such the one of the class reads the variables from a text file and the other classes use these variables for further processing.
The problem im facing is that im having trouble passing the variables from one class to another class, i did try "friend" class and also tried to use constructors but failed
to get the desired output.
The best i could do was
suppose i have class 1 and class 2, and i have a variable "A=10" declared and initialised in class 1, with the help of constructor i inherit it in class 2;
when i print it in class 1, it gives a correct output as 10 but when i print it in class 2 it gives a output as 293e30 (adress location)
Please guide me on how to this.
Thank you in advance

Code:

---

Class 1
{
public:
        membfunc()
        {
                int A;
                A=10;
        }
}

Class 2
{
public:
        membfunc2()
        {
                int B;
                B=A+10;
        }

        membfunc3()
        {
                int C, D;
                C=A+10;
                D=B+C;
        }
}

---

the expected output when printed should be
A=10, B=20, C=20, D=40.
but the output which im getting is
A=10, B=(262e12)+10

When posting code, please use code tags. Go Advanced, select the formatted code and click '#'.

Your code makes no sense and won't even compile. Class 2 doesn't inherit anything from Class 1 ?? In the code below, Class2 inherits from Class1 (Class2 is-a Class1) and Class3 includes a Class1 (Class3 has-a Class1). Consider

Code:

---

#include <iostream>
using namespace std;

class Class3;

class Class1 {
public:
        Class1(int i = 10) : A(i) { }

        friend Class3;

protected:
        int A;
};

class Class2 : public Class1 {
public:
        Class2() : Class1(5), B(A + 10) {}

        void display() const
        {
                cout << "A: " << A << " B: " << B << endl;
        }

private:
        int B;
};

class Class3 {
public:
        Class3(int c = 20) : c1(), C(c + 20) {}

        void display() const
        {
                cout << "A: " << c1.A << " C: " << C << endl;
        }

private:
        Class1 c1;
        int C;
};

int main()
{
        Class2 c2;
        c2.display();

        Class3 c3;
        c3.display();
}

---