title: C++ - Instantiating derived class and using base class's constructor
body: <p>I have a base class with a constructor that requires one parameter (string).  Then I have a derived class which also has its' own constructor.  I want to instantiate the derived class and be able to set the parameter of the base class's constructor as well.</p>
  
  <pre><code>class BaseClass {
      public:
          BaseClass (string a);
  };
  
  class DerivedClass : public BaseClass {
      public:
          DerivedClass (string b);
  };
  
  int main() {
      DerivedClass abc ("Hello");
  }
  </code></pre>
  
  <p>I'm not sure how to set the base class constructor's parameter when calling the derived class.</p>