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POLearning inheritance
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copied!<p>I am trying to understand inheritance and I need some help building two classes. The fist one is called A, the second one is called B. A has one private integer value "m_a". It has two constructors, the default one sets m_a to 5. and another one which takes as an argument an integer called m and sets m_a's value to m. As for member functions it will have two. The first one will return m_a. The second one will print "Hello from A!". Let's move on to B. B will have a private string m_s. A default constructor which will set m_s to "asd" or to anything other than an empty string and a constructor which will take as an argument a string and set m_s to it's value. As far as functions go, firstly B will have a function that will return m_s. It will have a function which will have the same name as the print "Hello from A" function in A which will override it and it will printout "Hello from B!" instead (is that polymorphism ?).</p> <p>Those are the classes needed. I have the following questions (I will post what I have created below) Firstly, is there any way I can get to the private data fileds from the base class. For example let's say I want to take the m_s variable, add it to another one and print out their sum. Is that possible ? (and how) </p> <p>Also when I try to create a class with a constructor different from the default one I get errors. I am obviously doing something wrong. The question is what.</p> <p>I think those are all of my questions for now, so it is time for me to post the source code.</p> <pre><code>#include <iostream> #include <string> using namespace std; class A { private: int m_a; public: A(){m_a = 5;} A(int m) { m_a = m; } void pm() { cout << "Hello from A!" << endl; } int get_a() { return m_a; } }; class B : A { private : string m_s; public: B(){m_s = "asd";} B(string s) { m_s = s; } void pm() { cout << "Hello from B!" << endl; } string get_s() { return m_s; } }; int main() { A a(10); a.pm(); cout << a.get_a() << endl; B b("asd"); b.pm(); cout << b.get_s() << endl; cout << b.get_a() << endl; return 0; } </code></pre>

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