Constructors are a type of member functions used to initialize objects of a class. They have the same name as the class name whose objects are initialized. Constructors are invoked whenever the object of its associated class are created. The scope operator is used in default form of constructors, and also can be declared even without "::" operator.

   #include <iostream.h>
   class value
    {             
      int m,n;
      public:
        value(int,int);
    void display(void)
     {
     cout << "m=" << m << '\n';
     cout << "n=" << n << '\n';
     }
    };
   value :: value (int x, int y)
     {
         m =x; n =y ;
     }
   int main ()
    {
      value int1(0,100);
      cout  << "Initialized values" << '\n';
      int1.display();
      return 0;
    }

   The sum of the values is::13 

In the above example the constructor "value" is used to initialize the values for "m,y".