Operators in C

Operators are special symbols used to perform operations on variables and values. These operations can be mathematical calculations, comparisons, logical checks, bit-level manipulations, and more.

The values or variables on which operators perform operations are called operands.

For example:

#include <stdio.h>

int main()
{
    int sum = 10 + 20;

    printf("%d", sum);

    return 0;
}

Output

30

In the above example, + is an operator and 10 and 20 are operands.

Unary, Binary, and Ternary Operators

Operators can be classified based on the number of operands they use.

Unary Operators

Unary operators work on a single operand.

Examples:

• Increment (++)

• Decrement (--)

• Logical NOT (!)

Example:

int a = 10;
a++;

Binary Operators

Binary operators work on two operands.

Examples:

• Addition (+)

• Subtraction (-)

• Multiplication (*)

• Division (/)

Example:

int sum = 10 + 20;

Ternary Operators

Ternary operators work on three operands.

The conditional operator (?:) is the only ternary operator in C.

Example:

int result = (10 > 5) ? 1 : 0;

Types of Operators in C

C provides several types of operators:

• Arithmetic Operators

• Relational Operators

• Logical Operators

• Bitwise Operators

• Assignment Operators

• Special Operators

Arithmetic Operators

Arithmetic operators are used to perform mathematical calculations.

The most commonly used arithmetic operators are:

• + Addition

• - Subtraction

• * Multiplication

• / Division

• % Modulus (Remainder)

• ++ Increment

• -- Decrement

Example

#include <stdio.h>

int main()
{
    int a = 25, b = 5;

    printf("a + b = %d\n", a + b);
    printf("a - b = %d\n", a - b);
    printf("a * b = %d\n", a * b);
    printf("a / b = %d\n", a / b);
    printf("a %% b = %d\n", a % b);

    return 0;
}

Output

a + b = 30
a - b = 20
a * b = 125
a / b = 5
a % b = 0

Relational Operators

Relational operators are used to compare two values.

These operators always return:

• 1 (True)

• 0 (False)

Relational operators include:

• < Less Than

• > Greater Than

• <= Less Than or Equal To

• >= Greater Than or Equal To

• == Equal To

• != Not Equal To

Example

#include <stdio.h>

int main()
{
    int a = 25, b = 5;

    printf("a > b = %d\n", a > b);
    printf("a < b = %d\n", a < b);
    printf("a == b = %d\n", a == b);

    return 0;
}

Output

a > b = 1
a < b = 0
a == b = 0

Logical Operators

Logical operators are used to combine multiple conditions.

The logical operators in C are:

Logical AND (&&)

Returns true only when both conditions are true.

a && b

Logical OR (||)

Returns true if at least one condition is true.

a || b

Logical NOT (!)

Reverses the result of a condition.

!a

Example

#include <stdio.h>

int main()
{
    int a = 25, b = 5;

    printf("a && b = %d\n", a && b);
    printf("a || b = %d\n", a || b);
    printf("!a = %d\n", !a);

    return 0;
}

Output

a && b = 1
a || b = 1
!a = 0

Bitwise Operators

Bitwise operators perform operations directly on binary bits.

Bitwise operators include:

• & Bitwise AND

• | Bitwise OR

• ^ Bitwise XOR

• ~ Bitwise NOT

• << Left Shift

• >> Right Shift

Example

#include <stdio.h>

int main()
{
    int a = 25, b = 5;

    printf("a & b = %d\n", a & b);
    printf("a | b = %d\n", a | b);
    printf("a ^ b = %d\n", a ^ b);

    return 0;
}

Output

a & b = 1
a | b = 29
a ^ b = 28

Assignment Operators

Assignment operators are used to assign values to variables.

Simple Assignment Operator

a = b;

Compound Assignment Operators

a += b;
a -= b;
a *= b;
a /= b;
a %= b;

These operators perform an operation and assignment in a single step.

Example

#include <stdio.h>

int main()
{
    int a = 10;

    a += 5;
    printf("%d\n", a);

    return 0;
}

Output

15

sizeof Operator

The sizeof operator is used to determine the size of a variable or data type in bytes.

Example

#include <stdio.h>

int main()
{
    int num = 10;

    printf("%zu", sizeof(num));

    return 0;
}

Output

4

Comma Operator (,)

The comma operator allows multiple expressions to be evaluated in a single statement.

Example

int a, b;
a = 10, b = 20;

Conditional Operator (?:)

The conditional operator is a shorthand version of the if...else statement.

Syntax

condition ? expression1 : expression2;

Example

int result = (10 > 5) ? 100 : 200;

Output

100

Dot (.) and Arrow (->) Operators

These operators are used with structures.

Dot Operator

Used with a structure variable.

student.name

Arrow Operator

Used with a structure pointer.

ptr->name

Cast Operator

The cast operator is used to convert one data type into another.

Example

float num = 10.75;

printf("%d", (int)num);

Output

10

Address-of (&) and Dereference (*) Operators

These operators are commonly used with pointers.

Address-of Operator (&)

Returns the memory address of a variable.

int num = 10;

printf("%p", &num);

Dereference Operator (*)

Accesses the value stored at a memory address.

int num = 10;
int *ptr = #

printf("%d", *ptr);

Output

10

Summary

• Operators are special symbols used to perform operations on variables and values.

• The values on which operators work are called operands.

• Operators are classified as unary, binary, and ternary operators.

• Arithmetic operators perform mathematical calculations.

• Relational operators compare values and return true or false.

• Logical operators combine multiple conditions.

• Bitwise operators work directly on binary bits.

• Assignment operators assign values to variables.

• Special operators such as sizeof, ?:, &, *, and type casting provide additional functionality in C.