Operators

 

C++ Operators

Operators are symbols that perform operations on variables and values. For example, + is an operator used for addition, while - is an operator used for subtraction.

Operators in C++ can be classified into 6 types:

1.    Arithmetic Operators

2.    Assignment Operators

3.    Relational Operators

4.    Logical Operators

5.    Bitwise Operators

6.    Other Operators

 

 

1. C++ Arithmetic Operators

Arithmetic operators are used to perform arithmetic operations on variables and data. For example,

a + b;

Here, the + operator is used to add two variables a and b. Similarly there are various other arithmetic operators in C++.

Operator	Operation
+	Addition
-	Subtraction
*	Multiplication
/	Division
%	Modulo Operation (Remainder after division)

 

 

Example 1: Arithmetic Operators

#include <iostream>

using namespace std;

 

int main() {

    int a, b;

    a = 7;

    b = 2;

 

    // printing the sum of a and b

    cout << "a + b = " << (a + b) << endl;

 

    // printing the difference of a and b

    cout << "a - b = " << (a - b) << endl;

 

    // printing the product of a and b

    cout << "a * b = " << (a * b) << endl;

 

    // printing the division of a by b

    cout << "a / b = " << (a / b) << endl;

 

    // printing the modulo of a by b

    cout << "a % b = " << (a % b) << endl;

 

    return 0;

}

Output

a + b = 9

a - b = 5

a * b = 14

a / b = 3

a % b = 1

 

% Modulo Operator

The modulo operator % computes the remainder. When a = 9 is divided by b = 4, the remainder is 1.

Note: The % operator can only be used with integers.

 

 

Increment and Decrement Operators

C++ also provides increment and decrement operators: ++ and -- respectively.

·       ++ increases the value of the operand by 1

·       -- decreases it by 1

For example,

int num = 5;

 

// increment operator

++num;  // 6

Here, the code ++num; increases the value of num by 1.

---

Example 2: Increment and Decrement Operators

// Working of increment and decrement operators

 

#include <iostream>

using namespace std;

 

int main() {

    int a = 10, b = 100, result_a, result_b;

 

    // incrementing a by 1 and storing the result in result_a

    result_a = ++a;

    cout << "result_a = " << result_a << endl;

 

 

    // decrementing b by 1 and storing the result in result_b  

    result_b = --b;

    cout << "result_b = " << result_b << endl;

 

    return 0;

}

Output

result_a = 11

result_b = 99

 

2. C++ Assignment Operators

In C++, assignment operators are used to assign values to variables. For example,

// assign 5 to a

a = 5;

Here, we have assigned a value of 5 to the variable a.

Operator	Example	Equivalent to
=	a = b;	a = b;
+=	a += b;	a = a + b;
-=	a -= b;	a = a - b;
*=	a *= b;	a = a * b;
/=	a /= b;	a = a / b;
%=	a %= b;	a = a % b;

---

Example 3: Assignment Operators

#include <iostream>

using namespace std;

 

int main() {

    int a, b;

 

    // 2 is assigned to a

    a = 2;

 

    // 7 is assigned to b

    b = 7;

 

    cout << "a = " << a << endl;

    cout << "b = " << b << endl;

    cout << "\nAfter a += b;" << endl;

 

    // assigning the sum of a and b to a

    a += b;  // a = a +b

    cout << "a = " << a << endl;

 

    return 0;

}

Output

a = 2

b = 7

 

After a += b;

a = 9

---

 

3. C++ Relational Operators

A relational operator is used to check the relationship between two operands. For example,

// checks if a is greater than b

a > b;

Here, > is a relational operator. It checks if a is greater than b or not.

If the relation is true, it returns 1 whereas if the relation is false, it returns 0.

Operator	Meaning	Example
==	Is Equal To	3 == 5 gives us false
!=	Not Equal To	3 != 5 gives us true
>	Greater Than	3 > 5 gives us false
<	Less Than	3 < 5 gives us true
>=	Greater Than or Equal To	3 >= 5 give us false
<=	Less Than or Equal To	3 <= 5 gives us true

---

 

Example 4: Relational Operators

#include <iostream>

using namespace std;

 

int main() {

    int a, b;

    a = 3;

    b = 5;

    bool result;

 

    result = (a == b);   // false

    cout << "3 == 5 is " << result << endl;

 

    result = (a != b);  // true

    cout << "3 != 5 is " << result << endl;

 

    result = a > b;   // false

    cout << "3 > 5 is " << result << endl;

 

    result = a < b;   // true

    cout << "3 < 5 is " << result << endl;

 

    result = a >= b;  // false

    cout << "3 >= 5 is " << result << endl;

 

    result = a <= b;  // true

    cout << "3 <= 5 is " << result << endl;

 

    return 0;

}

Output

3 == 5 is 0

3 != 5 is 1

3 > 5 is 0

3 < 5 is 1

3 >= 5 is 0

3 <= 5 is 1

Note: Relational operators are used in decision-making and loops.

---

 

4. C++ Logical Operators

Logical operators are used to check whether an expression is true or false. If the expression is true, it returns 1 whereas if the expression is false, it returns 0.

Operator	Example	Meaning
&&	expression1 && expression2	Logical AND. True only if all the operands are true.
||	expression1 || expression2	Logical OR. True if at least one of the operands is true.
!	!expression	Logical NOT. True only if the operand is false.

In C++, logical operators are commonly used in decision making. To further understand the logical operators, let's see the following examples,

Suppose,

a = 5

b = 8

 

Then,

 

(a > 3) && (b > 5) evaluates to true

(a > 3)  && (b < 5) evaluates to false

 

(a > 3) || (b > 5) evaluates to true

(a > 3) || (b < 5) evaluates to true

(a < 3) || (b < 5) evaluates to false

 

!(a < 3) evaluates to true

!(a > 3) evaluates to false

---

Example 5: Logical Operators

#include <iostream>

using namespace std;

 

int main() {

    bool result;

 

    result = (3 != 5) && (3 < 5);     // true

    cout << "(3 != 5) && (3 < 5) is " << result << endl;

 

    result = (3 == 5) && (3 < 5);    // false

    cout << "(3 == 5) && (3 < 5) is " << result << endl;

 

    result = (3 == 5) && (3 > 5);    // false

    cout << "(3 == 5) && (3 > 5) is " << result << endl;

 

    result = (3 != 5) || (3 < 5);    // true

    cout << "(3 != 5) || (3 < 5) is " << result << endl;

 

    result = (3 != 5) || (3 > 5);    // true

    cout << "(3 != 5) || (3 > 5) is " << result << endl;

 

    result = (3 == 5) || (3 > 5);    // false

    cout << "(3 == 5) || (3 > 5) is " << result << endl;

 

    result = !(5 == 2);    // true

    cout << "!(5 == 2) is " << result << endl;

 

    result = !(5 == 5);    // false

    cout << "!(5 == 5) is " << result << endl;

 

    return 0;

}

Output

(3 != 5) && (3 < 5) is 1

(3 == 5) && (3 < 5) is 0

(3 == 5) && (3 > 5) is 0

(3 != 5) || (3 < 5) is 1

(3 != 5) || (3 > 5) is 1

(3 == 5) || (3 > 5) is 0

!(5 == 2) is 1

!(5 == 5) is 0

 

5. C++ Bitwise Operators

In C++, bitwise operators are used to perform operations on individual bits. They can only be used alongside char and int data types.

Operator	Description
&	Binary AND
|	Binary OR
^	Binary XOR
~	Binary One's Complement
<<	Binary Shift Left
>>	Binary Shift Right

 

 

6. Other C++ Operators

Here's a list of some other common operators available in C++. We will learn about them in later tutorials.

Operator	Description	Example
sizeof	returns the size of data type	sizeof(int); // 4
?:	returns value based on the condition	string result = (5 > 0) ? "even" : "odd"; // "even"
&	represents memory address of the operand	# // address of num
.	accesses members of struct variables or class objects	s1.marks = 92;
->	used with pointers to access the class or struct variables	ptr->marks = 92;
<<	prints the output value	cout << 5;
>>	gets the input value	cin >> num;