C Operators Complete Practice Questions with Solutions

Introduction

Operators are symbols used to perform operations on values and variables in C. They allow programs to calculate numbers, compare values, combine conditions, assign values, and perform other operations. In this chapter, you will practice the main C operator categories through simple programs, including arithmetic, relational, logical, assignment, increment, decrement, and conditional operators. The examples are arranged from basic calculations to practical problems so beginners can build a strong understanding of how operators work. C Operators Complete Practice questions with solutions to help you understand the concepts.

Q1. Perform Basic Arithmetic Operations

Problem Statement

Write a C program that takes two numbers and performs addition, subtraction, multiplication, division, and modulus operations.

C Program

#include <stdio.h>

int main()
{
    int a = 20;
    int b = 6;

    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;
}

Sample Output

Addition = 26
Subtraction = 14
Multiplication = 120
Division = 3
Remainder = 2

Concepts Covered

Arithmetic operators
+
-
*
/
%
Integer division

Q2. Compare Two Numbers

Problem Statement

Write a C program to compare two numbers and display the results of different relational operations.

C Program

#include <stdio.h>

int main()
{
    int a = 20;
    int b = 15;

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

    return 0;
}

Sample Output

a == b : 0
a != b : 1
a > b  : 1
a &lt; b  : 0
a >= b : 1
a &lt;= b : 0

In C, a comparison produces 1 when it is true and 0 when it is false.

Concepts Covered

Relational operators
==
!=
>
<
>=
<=

Q3. Use Logical AND Operator

Problem Statement

A student passes only if their marks are at least 40 in both Mathematics and Science. Write a C program to check this condition using the logical AND operator.

C Program

#include <stdio.h>

int main()
{
    int math = 65;
    int science = 55;

    int result = (math >= 40) && (science >= 40);

    printf("Pass condition = %d", result);

    return 0;
}

Sample Output

Pass condition = 1

Concepts Covered

Logical operators
&&
Relational operators
Boolean result
Combining conditions

Q4. Use Logical OR Operator

Problem Statement

A student can participate in a special activity if they have either a score of at least 80 or an attendance percentage of at least 90. Write a C program using the logical OR operator.

C Program

#include <stdio.h>

int main()
{
    int marks = 75;
    int attendance = 92;

    int eligible = (marks >= 80) || (attendance >= 90);

    printf("Eligible = %d", eligible);

    return 0;
}

Sample Output

Eligible = 1

Concepts Covered

Logical OR
||
Relational operators
Multiple conditions

Q5. Use the Logical NOT Operator

Problem Statement

Create a C program that checks whether a number is not zero using the logical NOT operator.

C Program

#include <stdio.h>

int main()
{
    int number = 10;

    int result = !(number == 0);

    printf("Number is not zero = %d", result);

    return 0;
}

Sample Output

Number is not zero = 1

Concepts Covered

Logical NOT
!
Relational expression
Logical result

Q6. Use Assignment Operators

Problem Statement

Start with a value of 20 and use compound assignment operators to modify it.

C Program

#include <stdio.h>

int main()
{
    int number = 20;

    number += 5;
    printf("After += 5: %d\n", number);

    number -= 3;
    printf("After -= 3: %d\n", number);

    number *= 2;
    printf("After *= 2: %d\n", number);

    number /= 2;
    printf("After /= 2: %d\n", number);

    number %= 4;
    printf("After %%= 4: %d\n", number);

    return 0;
}

Sample Output

After += 5: 25
After -= 3: 22
After *= 2: 44
After /= 2: 22
After %= 4: 2

Concepts Covered

Assignment operators
=
+=
-=
*=
/=
%=

Q7. Use Increment and Decrement Operators

Problem Statement

Write a C program to demonstrate pre-increment, post-increment, pre-decrement, and post-decrement.

C Program

#include <stdio.h>

int main()
{
    int number = 10;

    printf("Original value = %d\n", number);

    printf("Post-increment = %d\n", number++);
    printf("After post-increment = %d\n", number);

    printf("Pre-increment = %d\n", ++number);

    printf("Post-decrement = %d\n", number--);
    printf("After post-decrement = %d\n", number);

    printf("Pre-decrement = %d\n", --number);

    return 0;
}

Sample Output

Original value = 10
Post-increment = 10
After post-increment = 11
Pre-increment = 12
Post-decrement = 12
After post-decrement = 11
Pre-decrement = 10

Concepts Covered

Increment operator ++
Decrement operator --
Pre-increment
Post-increment
Pre-decrement
Post-decrement

Q8. Use the Conditional Operator

Problem Statement

Write a C program to find the larger of two numbers using the conditional operator.

C Program

#include <stdio.h>

int main()
{
    int a = 45;
    int b = 70;

    int larger = (a > b) ? a : b;

    printf("Larger number = %d", larger);

    return 0;
}

Sample Output

Larger number = 70

Concepts Covered

Conditional operator
?:
Relational operator
Conditional expression

Q9. Calculate a Student’s Result Using Multiple Operators

Problem Statement

Write a C program that calculates a student’s total and average marks and checks whether the student passed all three subjects. A student must score at least 40 in every subject.

C Program

#include <stdio.h>

int main()
{
    int math = 75;
    int science = 68;
    int computer = 82;

    int total = math + science + computer;
    float average = total / 3.0;

    int passed = (math >= 40) &&
                 (science >= 40) &&
                 (computer >= 40);

    printf("Total = %d\n", total);
    printf("Average = %.2f\n", average);
    printf("Passed = %d", passed);

    return 0;
}

Sample Output

Total = 225
Average = 75.00
Passed = 1

Concepts Covered

Arithmetic operators
Relational operators
Logical AND
Assignment
Floating-point division
Multiple expressions

Q10. Build a Simple Operator-Based Calculator

Problem Statement

Write a C program that accepts two numbers from the user and displays their sum, difference, product, quotient, and remainder.

C Program

#include <stdio.h>

int main()
{
    int a, b;

    printf("Enter first number: ");
    scanf("%d", &a);

    printf("Enter second number: ");
    scanf("%d", &b);

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

    if (b != 0)
    {
        printf("Division = %.2f\n", (float)a / b);
        printf("Remainder = %d\n", a % b);
    }
    else
    {
        printf("Division and remainder are not possible with zero.");
    }

    return 0;
}

Sample Output

Enter first number: 25
Enter second number: 4

Addition = 29
Subtraction = 21
Multiplication = 100
Division = 6.25
Remainder = 1

Concepts Covered

Arithmetic operators
Relational operator
Assignment
Type casting
Division
Modulus
User input
Multiple operators
Basic if-else

Key Takeaways

Operators perform operations on values and variables.
Arithmetic operators are used for mathematical calculations.
Relational operators compare two values and produce 1 or 0.
Logical operators are used to combine or reverse conditions.
Assignment operators assign or update values.
++ increases a value by one, while -- decreases it by one.
Pre-increment changes the value before its expression is evaluated.
Post-increment uses the current value before increasing it.
The conditional operator ?: provides a compact way to choose between two expressions.
The modulus operator % returns the remainder of integer division.
Integer division can discard the fractional part, so type conversion may be needed when a decimal result is required.
Division and modulus by zero must be avoided.

FAQs

1. What are operators in C?

Operators are symbols that tell C to perform an operation on one or more operands.

For example:

int sum = a + b;

Here, + is an arithmetic operator.

2. What are the main types of operators in C?

Common operator categories include arithmetic, relational, logical, assignment, increment/decrement, conditional, and bitwise operators.

3. What is the difference between `=` and `==`?

= is the assignment operator. It assigns a value.

x = 10;

== is the equality operator. It compares two values.

x == 10;

4. What does `%` do in C?

With integer operands, % returns the remainder after division.

int result = 17 % 5;

The value of result is 2.

5. What is the difference between `++x` and `x++`?

++x is pre-increment: the value is increased before it is used in the surrounding expression.

x++ is post-increment: the current value is used first, and then the variable is increased.

6. What does the `&&` operator do?

&& is the logical AND operator. An expression using && is true only when both of its operands are true.

(age >= 18) && (citizen == 1)

7. What is the conditional operator in C?

The conditional operator ?: is a three-part operator that selects one of two expressions based on a condition.

int max = (a > b) ? a : b;

If a > b is true, a is selected; otherwise, b is selected.

Written by Shubhranshu Shekhar, who has trained 20000+ students in coding.

Rishabh Kumar

Introduction

Q1. Perform Basic Arithmetic Operations

Problem Statement

C Program

Sample Output

Concepts Covered

Q2. Compare Two Numbers

Problem Statement

C Program

Sample Output

Concepts Covered

Q3. Use Logical AND Operator

Problem Statement

C Program

Sample Output

Concepts Covered

Q4. Use Logical OR Operator

Problem Statement

C Program

Sample Output

Concepts Covered

Q5. Use the Logical NOT Operator

Problem Statement

C Program

Sample Output

Concepts Covered

Q6. Use Assignment Operators

Problem Statement

C Program

Sample Output

Concepts Covered

Q7. Use Increment and Decrement Operators

Problem Statement

C Program

Sample Output

Concepts Covered

Q8. Use the Conditional Operator

Problem Statement

C Program

Sample Output

Concepts Covered

Q9. Calculate a Student’s Result Using Multiple Operators

Problem Statement

C Program

Sample Output

Concepts Covered

Q10. Build a Simple Operator-Based Calculator

Problem Statement

C Program

Sample Output

Concepts Covered

Key Takeaways

FAQs

1. What are operators in C?

2. What are the main types of operators in C?

3. What is the difference between = and ==?

4. What does % do in C?

5. What is the difference between ++x and x++?

6. What does the && operator do?

7. What is the conditional operator in C?

Related Posts

3. What is the difference between `=` and `==`?

4. What does `%` do in C?

5. What is the difference between `++x` and `x++`?

6. What does the `&&` operator do?