Operators in C

Operators are symbols used to perform operations on variables and values. They tell the computer what action to perform.

Without operators, a program cannot calculate, compare, or make decisions. Understanding operators clearly is essential before moving further in C.

Why Operators Matter

Every meaningful program performs operations such as:

• Adding numbers
• Comparing values
• Making decisions
• Updating variables

All of this is done using operators.

Types of Operators in C

C provides several types of operators. In this lesson, we will focus on the most important ones.

• Arithmetic Operators
• Relational Operators
• Logical Operators
• Assignment Operators

1. Arithmetic Operators

Arithmetic operators are used to perform mathematical calculations.

• + Addition
• - Subtraction
• * Multiplication
• / Division
• % Modulus (remainder)

#include <stdio.h>

int main() {
    int a = 10, b = 3;

    printf("Addition: %d\n", a + b);
    printf("Subtraction: %d\n", a - b);
    printf("Multiplication: %d\n", a * b);
    printf("Division: %d\n", a / b);
    printf("Remainder: %d\n", a % b);

    return 0;
}

The modulus operator (%) is often used to check whether a number is even or odd.

2. Relational Operators

Relational operators are used to compare two values. They always return either true (1) or false (0).

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

#include <stdio.h>

int main() {
    int x = 5, y = 10;

    printf("%d\n", x > y);
    printf("%d\n", x < y);
    printf("%d\n", x == y);

    return 0;
}

3. Logical Operators

Logical operators are used when working with multiple conditions.

• && Logical AND
• || Logical OR
• ! Logical NOT

These operators are heavily used in decision making.

#include <stdio.h>

int main() {
    int age = 20;

    if (age >= 18 && age <= 60) {
        printf("Eligible\n");
    }

    return 0;
}

4. Assignment Operators

Assignment operators are used to assign values to variables.

• = Simple assignment
• += Add and assign
• -= Subtract and assign
• *= Multiply and assign
• /= Divide and assign

int a = 10;
a += 5;   // a = a + 5

Mini Practice

• Write a program to check if a number is even or odd
• Compare two numbers and print the larger one
• Use logical operators to validate age eligibility

Quick Quiz

Q1. Which operator gives the remainder?

The modulus (%) operator.

Q2. What does the == operator do?

It checks whether two values are equal.

Q3. Which operator is used for logical AND?

The && operator.

Q4. What is the output of 10 % 3?

1

Q5. Does relational operator return true or false?

Yes, it returns true (1) or false (0).