What is Overloading in C++?

Programming Language
#1

Creating two or more members having the same name but different in number or type of parameter is known as overloading.

C++ allows the overloading of:-

  • methods,
  • constructors, and
  • indexed properties

and is of two types:-

  • Function overloading - having two or more function with the same name, but different in parameters.

CODE:

class Cal {    
    public:    
static int add(int a,int b){      
        return a + b;      
    }      
static int add(int a, int b, int c)      
    {      
        return a + b + c;      
    }      
};     
int main(void) {    
    Cal C;                                                    //     class object declaration.   
    cout<<C.add(10, 20)<<endl;      
    cout<<C.add(12, 20, 23);     
   return 0;    
}
  • Operator overloading - operator is overloaded to provide the special meaning to the user-defined data type. Operator overloading is used to overload or redefines most of the operators available in C++

Some exceptions to this are:-

Scope operator (::), Sizeof, member selector(.), member pointer, selector(*), ternary operator(?:)

There are also some norms associated with overloading operators:-

  • Existing operators can only be overloaded.
  • The overloaded operator contains at least one operand of the user-defined data type.
  • When unary operators are overloaded through a member function take no explicit arguments, but, if they are overloaded by a friend function, takes one argument.
  • When binary operators are overloaded through a member function takes one explicit argument, and if they are overloaded through a friend function takes two explicit arguments.
class Test    
{    
   private:    
      int num;    
   public:    
       Test(): num(8){}    
       void operator ++()         {     
          num = num+2;     
       }    
       void Print() {     
           cout<<"The Count is: "<<num;     
       }    
};    
int main()    
{    
    Test tt;    
    ++tt;  // calling of a function "void operator ++()"    
    tt.Print();    
    return 0;    
}