Using Functions and Classes with C++

Functions

Function Prototype:

<return class> <function name> (class1> <name1>, ..., <classN> <nameN>);

Function Declaration:

<return class> <function name> (class1> <name1>, ..., <classN> <nameN>);
{
   <function body goes here>
}

Example:
int Max (int num1, int num2);
{
   if (num1 >= num2) {
      return num1;
   }
   else {
      return num2;
   }
}

Classes:

Class Declaration:
class <class name>
{
   private:
      <private member data>
      <private member functions>
   public:
      <public member data>
      <public member functions>
};

For example,

class Rectangle {
   private:
      float length;
      float width;
   public:
      void setLength(float inLength);
      void setWidth(float inWidth);
      float getLength();
      float getWidth();
      float getArea();
}

With this rectangle declaration, we can use the following code:

Rectangle square;
square.setLength(2.0);
square.setWidth(2.0);
cout << "Rectangle has length " << square.getLength() << endl;
cout << "Rectangle has width " << square.getWidth() << endl;
cout << "Area of rectangel is " << square.getArea() << endl;