What are Interfaces in C++?

Programming Language
#1

An interface describes the behavior or capabilities of a C++ class without committing to a particular implementation of that class.

Interfaces are implemented using abstract classes.

A class is made abstract by declaring at least one of its functions as pure virtual function. A pure virtual function is specified by placing “= 0” in its declaration as follows −

CODE:

using namespace std;  
 class Shape    
{    
    public:   
    virtual void draw()=0;    
};    
 class Rectangle: Shape    
{    
    public:  
     void draw()    
    {    
        cout < <"drawing rectangle..." < <endl;    
    }    
};    
class Circle : Shape    
{    
    public:  
     void draw()    
    {    
        cout <<"drawing circle..." < <endl;    
    }    
};    
int main( ) {  
    Rectangle rec;  
    Circle cir;  
    rec.draw();    
    cir.draw();   
   return 0;  
}