Operators

In programming, we often need to perform operations such as addition, subtraction, comparison, or assignment.

C provides special symbols called operators to perform these operations.

What is an Operator?

An operator is a symbol that tells the compiler to perform a specific operation on one or more values.

For example:

int sum = 10 + 20;

Here, + is an operator that adds two numbers.

The values on which an operator works are called operands.

10 + 20
↑    ↑
Operand

+ → Operator

Types of Operators in C

C operators can be grouped into several categories:

Let's understand the most important ones.

1. Arithmetic Operators

These are used for mathematical calculations.

Example:

int a = 10;
int b = 3;

printf("%d", a + b);

Output:

13

The % operator gives the remainder:

printf("%d", 10 % 3);

Output:

1

2. Assignment Operators

Assignment operators are used to assign or update values.

The basic assignment operator is =.

int age = 20;

Other assignment operators include:

age += 5;   // age = age + 5
age -= 5;   // age = age - 5
age *= 2;   // age = age * 2
age /= 2;   // age = age / 2

3. Relational Operators

Relational operators are used to compare values.

>   Greater than
<   Less than
>=  Greater than or equal to
<=  Less than or equal to
==  Equal to
!=  Not equal to

For example:

int age = 20;

printf("%d", age > 18);

The result is non-zero when the condition is true and 0 when it is false. In typical C programs, 1 is commonly used to represent true.

4. Logical Operators

Logical operators are used to combine or reverse conditions.

Example:

int age = 20;

printf("%d", age >= 18 && age <= 60);

Both conditions are true, so the result is true.

5. Increment and Decrement

These operators increase or decrease a value by 1.

int count = 5;

count++;

Now count becomes 6.

Similarly:

count--;

decreases it by 1.

You'll commonly see these operators in loops.

6. Bitwise Operators

Bitwise operators work directly with the individual bits of integer values.

Examples include:

&   AND
|   OR
^   XOR
~   NOT
<<  Left shift
>>  Right shift

For example:

int a = 5;
int b = 3;

printf("%d", a & b);

Bitwise operators are especially useful in areas such as embedded systems, low-level programming, and bit manipulation.

7. Conditional Operator

The conditional operator ?: is a short way to choose between two expressions based on a condition.

int age = 20;

int result = (age >= 18) ? 1 : 0;

If age >= 18 is true, result gets 1; otherwise, it gets 0.

Simple Example

Let's combine a few operators:

#include <stdio.h>

int main()
{
    int a = 10;
    int b = 5;

    printf("Sum = %d\n", a + b);
    printf("Difference = %d\n", a - b);
    printf("Product = %d\n", a * b);
    printf("Remainder = %d\n", a % b);

    return 0;
}

Output:

Sum = 15
Difference = 5
Product = 50
Remainder = 0

In Simple Words

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

For example:

10 + 5

Here, + is the operator, while 10 and 5 are the operands.

Operators are one of the most important parts of C because almost every program uses them for calculations, comparisons, conditions, and data manipulation.