C Exam Questions

This lesson covers C exam questions frequently asked in theory, practical, and viva sections. Use it to target study for high scores.

• What is C programming? Explain its key features.
• Who developed C language?
• Structure of a C program (describe components).
• Tokens in C: types include keywords, identifiers, constants, operators, special symbols.
• Compiler vs Interpreter
• Variables and Constants: definitions and usages.
• Data types: int, float, char, double
• Keywords: definition with examples (int, if, else, while)
• Local vs Global variables
• Operators: types with examples (+, -, *, /, %, ==, etc.)
• Header File: what it is and examples (#include <stdio.h>)

• if, if-else, and switch: differences.
• Loop syntax and examples for for, while, and do-while loops.
• break vs continue: distinction.
• Nested loops: structure and examples.
• Writing programs using switch-case

• What is a function?
• Types: library vs user-defined.
• Call by Value vs Call by Reference
• Recursion: meaning and example.
• Function Prototype: purpose and syntax.

Common Function Programs:

• Program to find factorial using function.
• Program to check if a number is prime using function.

• What is an array? Types described (1D, 2D).
• 1D vs 2D array: usage and syntax.
• Array Initialization: methods.
• Passing array to a function

Common Array Programs:

• Find the largest element.
• Reverse an array.
• Matrix addition.
• Matrix multiplication.

• String in C: definition.
• Char array vs String: comparison.
• String Functions: strlen(), strcpy(), strcmp().

Common String Programs:

• Reverse a string.
• Check if a string is a palindrome.
• Count vowels and consonants.

• Pointer: definition, declaration, and initialization.
• Pointer arithmetic
• Pointer to pointer: usage.
• Pointer vs Array: differences.

Common Pointer Programs:

• Swap two numbers using pointers.
• Access an array using a pointer.

• Structure: definition, example.
• Structure vs Union: memory and usage differences.
• Nested Structures: example of a structure within a structure.
• Array of Structures: definition and usage.

Common Structures Program:

• Store and display student details using structure.

• File handling in C: purpose.
• File modes: 'r', 'w', 'a'.
• Functions: fopen(), fclose(), fprintf(), fscanf().

Common File Handling Programs:

• Write data to a file.
• Read data from a file.

• Header files: definition and common files.
• #include directive: purpose.
• Macros: what they are and how to define.
• #define vs variables: differences.

• Hello World
• Even or Odd number
• Prime number
• Factorial of a number
• Fibonacci series
• Reverse a number
• Palindrome number
• Armstrong number
• Swap two numbers (with & without third variable)
• Sum of digits

Examiner may give a code and ask you to predict output. Practice examples:

c Run in compiler
#include <stdio.h>
int main() {
    int a = 5;
    printf("%d %d %d", a, a++, ++a);
    return 0;
}

text
5 5 7

Focus areas:

• Increment operators (++ and --)
• Operator precedence
• Loop outputs

• Why is C called a middle-level language?
• Difference between = and ==
• What is a NULL pointer?
• What is segmentation fault?
• Why use return 0 in main()?

Focus on these topics for scoring well:

• Pointers (theory and programs)
• Arrays & Strings
• Functions & Recursion
• Loops (for, while)
• Basic programs (prime, factorial, Fibonacci)

• Practice writing code, not just reading.
• Understand the logic, do not memorize.
• Solve previous year papers.
• Write proper syntax, as marks are deducted for mistakes.

1. Most exams cover core concepts: variables, loops, arrays, functions, pointers, and file handling.
2. Practice both theory and practical coding for comprehensive preparation.
3. Output-based prediction questions are common in exams.
4. Proficiency in functions, pointers, and arrays provides a clear edge.
5. Syntax precision is essential—minor mistakes can cost marks.

1. Write a program to check if a number is prime using a user-defined function.
2. Implement matrix multiplication using 2D arrays in C.
3. Swap two variables using pointers.
4. Write a code to count vowels and consonants in a string.
5. Predict the output of a code that uses both a++ and ++a in a printf statement.

1. Always declare variables before using them.
2. Regularly comment your code for better readability.
3. Pay attention to operator precedence in expressions.
4. Memorize syntax for loops, if-else, and function declarations.
5. Practice output-based and error-finding questions under timed conditions.
6. Revise library functions and commonly used headers before exams.