C++ Tutorial Home Page

C++ Operator Overloading

What is operator overloading
Rules for overloading Operators
Operator Overloading restrictions
List of operators that cannot be overloaded.
Overloading Unary operator
Overloading increment operator(++)
Overloading decrement operator(–)
Overloading unary operator(-)
Overloading increment operator(++) postfix
Overloading decrement operator(–) postfix
Overloading increment operator (++) with friend function
Overloading increment operator (–) with friend function
Increment the time using ++
Decrement the time using ++
Overloading Binary operator(+,-,*,/,%)
Add two object using “+” operator with friend function
Overloading “-” operator
Overloading “*” operator
Overloading “/” operator
Overloading “%” operator
overloading all (+,-,*,/,%)
Overloading “+” operator with friend function
class distance (feet,inches) with “+” operator
class distance (feet,inches) with “+” operator with friend function
class distance (km,m) with “+” operator
class distance (km,m) with “+” operator with friend function
class distance (m,cm) with “+” operator
class distance (m,cm) with “+” operator with friend function
class distance (km,m,cm) with “+” operator
class distance (km,m,cm) with “+” operator with friend function
class distance (km,m,cm,mm) with “+” operator
class distance (km,m,cm,mm) with “+” operator with friend function
class time(hh,mm,ss) with “+” operator
class time(hh,mm,ss) with “+” operator with friend function
class complex(real,ing) with “+” operator
class complex(real,ing) with “+” operator with friend function
class string(str) with “+” operator
class string(str) with “+” operator with friend function
overloading “+=” operator

C++:Overloading Binary Operators 

Overloading Binary Operators      ( +, -, *, /, % )

Example:1
C++ program to overload binary operator “+”. (Add two objects using overloaded operator “+”.)

// to overload + operator
// add two objects
#include<iostream>
#include<conio.h>
using namespace std;
class sample
{
private:
	int a;
public:
	sample();
	sample(int n);
	void get();
	void disp();
	sample operator+(sample s);
};
sample::sample()
{
	a=0;
}
sample::sample(int n)
{
	a=n;
}
void sample::get()
{
	cout<<"Enter the value of a ";
	cin>>a;
}
void sample::disp()
{
	cout<<"a= "<<a<<endl;
}
sample sample::operator+(sample s)
{
	sample t;
	t.a=a+s.a;
	return(t);
}

int main()
{
  sample s1,s2,s3;
  s1.get();s2.get();
  s1.disp();s2.disp();
  s3=s1+s2;//s3=s1.operator+(S2);
  s3.disp();
  getch();
  return(0);
}

Output:

Enter the value of a 10
Enter the value of a 20
a= 10
a= 20
a= 30

Example:2
C++ program to overload binary operator “-“.

// to overload - operator
// add two objects
#include<iostream>
#include<conio.h>
using namespace std;
class sample
{
private:
	int a;
public:
	sample();
	sample(int n);
	void get();
	void disp();
	sample operator-(sample s);
};
sample::sample()
{
	a=0;
}
sample::sample(int n)
{
	a=n;
}
void sample::get()
{
	cout<<"Enter the value of a ";
	cin>>a;
}
void sample::disp()
{
	cout<<"a= "<<a<<endl;
}
sample sample::operator-(sample s)
{
	sample t;
	t.a=a-s.a;
	return(t);
}

int main()
{
  sample s1,s2,s3;
  s1.get();s2.get();
  s1.disp();s2.disp();
  s3=s1-s2;//s3=s1.operator-(S2);
  s3.disp();
  getch();
  return(0);
}

Output:

Enter the value of a 10
Enter the value of a 20
a= 10
a= 20
a= -10

Example:3
C++ program to overload binary operator “*”.

// to overload * operator
// with two objects
#include<iostream>
#include<conio.h>
using namespace std;
class sample
{
private:
	int a;
public:
	sample();
	sample(int n);
	void get();
	void disp();
	sample operator*(sample s);
};
sample::sample()
{
	a=0;
}
sample::sample(int n)
{
	a=n;
}
void sample::get()
{
	cout<<"Enter the value of a ";
	cin>>a;
}
void sample::disp()
{
	cout<<"a= "<<a<<endl;
}
sample sample::operator*(sample s)
{
	sample t;
	t.a=a*s.a;
	return(t);
}

int main()
{
  sample s1,s2,s3;
  s1.get();s2.get();
  s1.disp();s2.disp();
  s3=s1*s2;//s3=s1.operator*(S2);
  s3.disp();
  getch();
  return(0);
}

Output:

Enter the value of a 10
Enter the value of a 20
a= 10
a= 20
a= 200