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In this tutorial, we will learn about the different types of operators in C++ with the help of examples. In programming, an operator is a symbol that operates on a value or a variable.

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

Here, the operators +, - and * compute addition, subtraction, and multiplication respectively as we might have expected.

/ Division Operator

As we can see from the above example, if an integer is divided by another integer, we will get the quotient. However, if either divisor or dividend is a floating-point number, we will get the result in decimals.

In C++,

  • 7/2 is 3
  • 7.0 / 2 is 3.5
  • 7 / 2.0 is 3.5
  • 7.0 / 2.0 is 3.5

% 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

In the above program, we have used the ++ and – operators as prefixes (++a and –b). However, we can also use these operators as postfix (a++ and b–).

To learn more, visit increment and decrement operators.

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

Explanation of logical operator program

  • (3 != 5) && (3 < 5) evaluates to 1 because both operands (3 != 5) and (3 < 5) are 1 (true).
  • (3 == 5) && (3 < 5) evaluates to 0 because the operand (3 == 5) is 0 (false).
  • (3 == 5) && (3 > 5) evaluates to 0 because both operands (3 == 5) and (3 > 5) are 0 (false).
  • (3 != 5) || (3 < 5) evaluates to 1 because both operands (3 != 5) and (3 < 5) are 1 (true).
  • (3 != 5) || (3 > 5) evaluates to 1 because the operand (3 != 5) is 1 (true).
  • (3 == 5) || (3 > 5) evaluates to 0 because both operands (3 == 5) and (3 > 5) are 0 (false).
  • !(5 == 2) evaluates to 1 because the operand (5 == 2) is 0 (false).
  • !(5 == 5) evaluates to 0 because the operand (5 == 5) is 1 (true).

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

To learn more, visit C++ bitwise operators.

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 &num; // 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;

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