100 Interview Questions C
Tags: cprogramming, interviewquestion
Published: 2023-10-18 10:01:28

# 100 Interview Questions - 

[View on GitHub](https://github.com/Pankaj-Str/C-Interview-Questions/blob/main/README.md)

1. **Question 1:**
   **Question:** Write a C program that prints numbers from 1 to 10 using a `for` loop.
   **Expected Output:**
   ```
   1 2 3 4 5 6 7 8 9 10
   ```

2. **Question 2:**
   **Question:** Create a C program that prints the even numbers from 2 to 20 using a `while` loop.
   **Expected Output:**
   ```
   2 4 6 8 10 12 14 16 18 20
   ```

3. **Question 3:**
   **Question:** Develop a program that calculates the sum of numbers from 1 to 100 using a `for` loop.
   **Expected Output:**
   ```
   The sum of numbers from 1 to 100 is 5050.
   ```

4. **Question 4:**
   **Question:** Write a C program that prints the first 10 terms of the Fibonacci sequence using a `do-while` loop.
   **Expected Output:**
   ```
   Fibonacci series: 0 1 1 2 3 5 8 13 21 34
   ```

5. **Question 5:**
   **Question:** Create a program that prompts the user to enter a positive integer and then prints the multiplication table for that number from 1 to 10 using a `for` loop.
   **Expected Output:**
   ```
   Enter a number: 7
   Multiplication table for 7:
   7 x 1 = 7
   7 x 2 = 14
   ...
   7 x 10 = 70
   ```

6. **Question 6:**
   **Question:** Develop a C program that prints a pattern of asterisks in the shape of a right-angled triangle using nested `for` loops.
   **Expected Output:**
   ```
   *
   **
   ***
   ****
   *****
   ```

7. **Question 7:**
   **Question:** Write a program that calculates the factorial of a user-entered number using a `while` loop.
   **Expected Output:**
   ```
   Enter a number: 5
   The factorial of 5 is 120.
   ```

8. **Question 8:**
   **Question:** Create a C program that checks if a user-entered number is a prime number using a `for` loop.
   **Expected Output:**
   ```
   Enter a number: 17
   17 is a prime number.
   ```

9. **Question 9:**
   **Question:** Develop a program that finds and displays the prime numbers in a given range (e.g., 1 to 100) using a `for` loop.
   **Expected Output:**
   ```
   Prime numbers in the range 1 to 100 are: 2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97
   ```

10. **Question 10:**
    **Question:** Write a C program that prints the ASCII values and characters for all printable characters (from ' ' to '~') using a `for` loop.
    **Expected Output:**
    ```
    ASCII values and characters for printable characters:
    ' ' (Space) - ASCII: 32
    '!' - ASCII: 33
    '"' - ASCII: 34
    ...
    '~' - ASCII: 126
    ```


11. **Question 11:**
    **Question:** Create a C program that calculates the sum of all even numbers between 1 and 50 using a `for` loop.
    **Expected Output:**
    ```
    The sum of even numbers from 1 to 50 is 650.
    ```

12. **Question 12:**
    **Question:** Write a C program that checks if a user-entered number is a perfect number. A perfect number is a positive integer that is equal to the sum of its proper divisors (excluding itself).
    **Expected Output:**
    ```
    Enter a number: 28
    28 is a perfect number.
    ```

13. **Question 13:**
    **Question:** Develop a program that calculates the factorial of a user-entered number using a `do-while` loop.
    **Expected Output:**
    ```
    Enter a number: 6
    The factorial of 6 is 720.
    ```

14. **Question 14:**
    **Question:** Create a C program that prints the squares of numbers from 1 to 10 using a `for` loop.
    **Expected Output:**
    ```
    1^2 = 1
    2^2 = 4
    3^2 = 9
    ...
    10^2 = 100
    ```

15. **Question 15:**
    **Question:** Write a C program that calculates the sum of a geometric series (1 + 2 + 4 + 8 + ... + 2^n) using a `for` loop. Prompt the user for the number of terms (n).
    **Expected Output:**
    ```
    Enter the number of terms (n): 5
    The sum of the geometric series is 31.
    ```

16. **Question 16:**
    **Question:** Develop a C program that prints the first n terms of the square root series (1, sqrt(2), sqrt(3), ...) using a `for` loop.
    **Expected Output:**
    ```
    Enter the number of terms (n): 4
    Square root series: 1.000 1.414 1.732 2.000
    ```

17. **Question 17:**
    **Question:** Create a program that calculates the sum of an arithmetic series (3 + 7 + 11 + ... + 3n - 1) using a `for` loop. Prompt the user for the number of terms (n).
    **Expected Output:**
    ```
    Enter the number of terms (n): 5
    The sum of the arithmetic series is 75.
    ```

18. **Question 18:**
    **Question:** Write a C program that prints the numbers from 100 to 1 in reverse order using a `while` loop.
    **Expected Output:**
    ```
    100 99 98 97 96 ... 4 3 2 1
    ```

19. **Question 19:**
    **Question:** Develop a program that generates and displays the Collatz sequence starting from a user-entered number. The Collatz sequence for a positive integer n is defined as follows: if n is even, divide it by 2; if n is odd, multiply it by 3 and add 1.
    **Expected Output:**
    ```
    Enter a number: 10
    Collatz sequence: 10 5 16 8 4 2 1
    ```

20. **Question 20:**
    **Question:** Create a C program that calculates and displays the GCD (greatest common divisor) of two user-entered numbers using the Euclidean algorithm in a `while` loop.
    **Expected Output:**
    ```
    Enter the first number: 24
    Enter the second number: 18
    The GCD of 24 and 18 is 6.
    ```

21. **Question 21:**
    **Question:** Write a C program to check if a user-entered number is a palindrome. A palindrome is a number that reads the same forwards and backwards.
    **Expected Output:**
    ```
    Enter a number: 121
    121 is a palindrome.
    ```

22. **Question 22:**
    **Question:** Create a C program that prints a pattern of stars in the shape of a diamond using nested `for` loops.
    **Expected Output:**
    ```
       *
      ***
     *****
    *******
     *****
      ***
       *
    ```

23. **Question 23:**
    **Question:** Develop a program that generates and displays a random number between 1 and 100. Prompt the user to guess the number, and provide hints.
    **Expected Output:**
    ```
    Guess the number (1-100): 50
    Try higher.
    Guess the number (1-100): 75
    Try lower.
    Guess the number (1-100): 63
    Congratulations! You guessed the number (63).
    ```

24. **Question 24:**
    **Question:** Write a C program that calculates the sum of the series 1 - 1/2 + 1/3 - 1/4 + ... - 1/n for a user-entered positive integer n.
    **Expected Output:**
    ```
    Enter a positive integer (n): 5
    The sum of the series is -0.78333.
    ```

25. **Question 25:**
    **Question:** Create a C program that simulates a simple game of rock-paper-scissors. The user plays against the computer.
    **Expected Output:**
    ```
    Choose your move (rock, paper, scissors): rock
    Computer's move: scissors
    You win!
    ```

26. **Question 26:**
    **Question:** Develop a program that calculates the value of π using the Leibniz formula. Prompt the user for the number of terms (n) to use in the formula.
    **Expected Output:**
    ```
    Enter the number of terms (n): 1000000
    The value of π is approximately 3.14159.
    ```

27. **Question 27:**
    **Question:** Write a C program that generates a random password of a specified length (e.g., 8 characters) containing a mix of letters (both uppercase and lowercase) and numbers.
    **Expected Output:**
    ```
    Your random password: K4rW8p7X
    ```

28. **Question 28:**
    **Question:** Create a C program that simulates a simple guessing game. The program generates a random number between 1 and 100, and the user must guess it within a limited number of attempts.
    **Expected Output:**
    ```
    Guess the number (1-100). You have 5 attempts.
    Attempt 1: 50
    Try higher.
    Attempt 2: 75
    Try lower.
    ...
    Congratulations! You guessed the number (63) in 4 attempts.
    ```

29. **Question 29:**
    **Question:** Develop a program that calculates the sum of all prime numbers between 1 and 100 using a `for` loop.
    **Expected Output:**
    ```
    The sum of prime numbers between 1 and 100 is 1060.
    ```

30. **Question 30:**
    **Question:** Write a C program that generates and displays a magic square of order 3. A magic square is a square matrix in which the sum of the numbers in each row, column, and both main diagonals is the same.
    **Expected Output:**
    ```
    Magic Square:
    2 7 6
    9 5 1
    4 3 8
    ```

31. **Question 31:**
    **Question:** Create a C program that prints a right-angled triangle pattern of asterisks using nested `for` loops.
    **Expected Output:**
    ```
    *
    **
    ***
    ****
    *****
    ```

32. **Question 32:**
    **Question:** Develop a program that prints a hollow square pattern of asterisks with a user-specified side length.
    **Expected Output:**
    ```
    Enter the side length of the square: 5
    *****
    *   *
    *   *
    *   *
    *****
    ```

33. **Question 33:**
    **Question:** Write a C program that prints a mirrored right-angled triangle pattern of numbers.
    **Expected Output:**
    ```
        1
       12
      123
     1234
    12345
    ```

34. **Question 34:**
    **Question:** Create a program that prints a pyramid pattern of asterisks with a user-specified height.
    **Expected Output:**
    ```
        *
       ***
      *****
     *******
    *********
    ```

35. **Question 35:**
    **Question:** Develop a C program that prints a diamond pattern of numbers with a user-specified number of rows.
    **Expected Output:**
    ```
        1
       121
      12321
     1234321
    123454321
     1234321
      12321
       121
        1
    ```

36. **Question 36:**
    **Question:** Write a C program that prints a right-angled triangle pattern of uppercase letters starting from 'A'.
    **Expected Output:**
    ```
    A
    AB
    ABC
    ABCD
    ABCDE
    ```

37. **Question 37:**
    **Question:** Create a program that prints a hollow right-angled triangle pattern of asterisks with a user-specified height.
    **Expected Output:**
    ```
    Enter the height of the triangle: 5
    *
    **
    * *
    *  *
    *****
    ```

38. **Question 38:**
    **Question:** Develop a C program that prints an inverted pyramid pattern of numbers.
    **Expected Output:**
    ```
    12345
     1234
      123
       12
        1
    ```

39. **Question 39:**
    **Question:** Write a program that prints a square pattern of numbers with each row starting from 1 and incrementing by 1.
    **Expected Output:**
    ```
    12345
    12345
    12345
    12345
    12345
    ```

40. **Question 40:**
    **Question:** Create a C program that prints a pattern of the letter 'X' formed by asterisks.
    **Expected Output:**
    ```
    *       *
     *     *
      *   *
       * *
        *
       * *
      *   *
     *     *
    *       *
    ```

41. **Question 41:**
    **Question:** Write a C program to calculate the sum of the first 10 natural numbers using a `while` loop.
    **Expected Output:**
    ```
    The sum of the first 10 natural numbers is 55.
    ```

42. **Question 42:**
    **Question:** Create a C program that prints a hollow square pattern of asterisks with a user-specified side length.
    **Expected Output:**
    ```
    Enter the side length of the square: 5
    *****
    *   *
    *   *
    *   *
    *****
    ```

43. **Question 43:**
    **Question:** Write a C program that checks if a given number is a power of two (2^n).
    **Expected Output:**
    ```
    Enter a number: 16
    16 is a power of 2.
    ```

44. **Question 44:**
    **Question:** Create a C program to find the factorial of a user-entered number using a `while` loop.
    **Expected Output:**
    ```
    Enter a number: 5
    The factorial of 5 is 120.
    ```

45. **Question 45:**
    **Question:** Develop a program that calculates the sum of all odd numbers from 1 to 100 using a `for` loop.
    **Expected Output:**
    ```
    The sum of odd numbers from 1 to 100 is 2500.
    ```

46. **Question 46:**
    **Question:** Write a C program that calculates the sum of the digits of a user-entered integer.
    **Expected Output:**
    ```
    Enter an integer: 12345
    The sum of the digits is 15.
    ```

47. **Question 47:**
    **Question:** Create a program that calculates the LCM (Least Common Multiple) of two user-entered numbers.
    **Expected Output:**
    ```
    Enter two numbers (separated by a space): 12 18
    The LCM of 12 and 18 is 36.
    ```

48. **Question 48:**
    **Question:** Develop a C program that checks if a user-entered string is a palindrome (reads the same forwards and backwards).
    **Expected Output:**
    ```
    Enter a string: radar
    "radar" is a palindrome.
    ```

49. **Question 49:**
    **Question:** Write a C program that calculates the sum of all the multiples of 3 and 5 between 1 and 100.
    **Expected Output:**
    ```
    The sum of multiples of 3 and 5 between 1 and 100 is 2418.
    ```

50. **Question 50:**
    **Question:** Create a program that finds and displays the first N prime numbers.
    **Expected Output:**
    ```
    Enter the value of N: 10
    The first 10 prime numbers are: 2 3 5 7 11 13 17 19 23 29
    ```

51. **Question 51:**
    **Question:** Develop a program that checks if a user-entered year is a leap year using a logical operator.
    **Expected Output:**
    ```
    Enter a year: 2024
    2024 is a leap year.
    ```

52. **Question 52:**
    **Question:** Write a C program that calculates and displays the GCD (greatest common divisor) of two user-entered numbers.
    **Expected Output:**
    ```
    Enter two numbers (separated by a space): 24 18
    The GCD of 24 and 18 is 6.
    ```

53. **Question 53:**
    **Question:** Create a program that calculates the sum of squares of the first N natural numbers.
    **Expected Output:**
    ```
    Enter the value of N: 4
    The sum of squares of the first 4 natural numbers is 30.
    ```

54. **Question 54:**
    **Question:** Develop a program that finds the smallest and largest elements in an array of integers.
    **Expected Output:**
    ```
    Enter the number of elements in the array: 6
    Enter the elements (separated by spaces): 18 7 42 10 31 55
    The smallest element in the array is 7, and the largest element is 55.
    ```

55. **Question 55:**
    **Question:** Write a C program that generates and displays a random password of a specified length (e.g., 8 characters) using a logical approach.
    **Expected Output:**
    ```
    Your random password: K4rW8p7X
    ```

56. **Question 56:**
    **Question:** Create a program that checks if a user-entered number is a perfect number.
    **Expected Output:**
    ```
    Enter a number: 28
    28 is a perfect number.
    ```

57. **Question 57:**
    **Question:** Develop a C program that prints a pattern of stars in the shape of a right-angled triangle using nested `for` loops.
    **Expected Output:**
    ```
    *
    **
    ***
    ****
    *****
    ```

58. **Question 58:**
    **Question:** Write a program that calculates the sum of even numbers between 1 and 50 using a `while` loop.
    **Expected Output:**
    ```
    The sum of even numbers from 1 to 50 is 650.
    ```

59. **Question 59:**
    **Question:** Create a C program that checks if a given number is a palindrome using a logical approach.
    **Expected Output:**
    ```
    Enter a number: 121
    121 is a palindrome.
    ```

60. **Question 60:**
    **Question:** Write a C program that checks if a user-entered string is a palindrome using logical operations.
    **Expected Output:**
    ```
    Enter a string: radar
    "radar" is a palindrome.
    ```

61. **Question 61:**
    **Question:** Develop a C program that finds and displays the first N Fibonacci numbers.
    **Expected Output:**
    ```
    Enter the value of N: 8
    The first 8 Fibonacci numbers are: 0 1 1 2 3 5 8 13
    ```

62. **Question 62:**
    **Question:** Write a C program to reverse a user-entered string without using any built-in string functions.
    **Expected Output:**
    ```
    Enter a string: programming
    Reversed string: gnimmargorp
    ```

63. **Question 63:**
    **Question:** Create a program that checks if a given year is a leap year or not using a logical approach.
    **Expected Output:**
    ```
    Enter a year: 2100
    2100 is not a leap year.
    ```

64. **Question 64:**
    **Question:** Develop a C program that calculates the product of digits in a user-entered integer.
    **Expected Output:**
    ```
    Enter an integer: 12345
    The product of the digits is 120.
    ```

65. **Question 65:**
    **Question:** Write a program that determines if a user-entered number is prime or composite.
    **Expected Output:**
    ```
    Enter a number: 17
    17 is a prime number.
    ```

66. **Question 66:**
    **Question:** Create a C program that counts and displays the number of words in a user-entered sentence.
    **Expected Output:**
    ```
    Enter a sentence: This is a sample sentence.
    The number of words in the sentence is 5.
    ```

67. **Question 67:**
    **Question:** Develop a program that calculates the sum of all natural numbers divisible by 3 or 5 between 1 and 100.
    **Expected Output:**
    ```
    The sum of natural numbers divisible by 3 or 5 between 1 and 100 is 2418.
    ```

68. **Question 68:**
    **Question:** Write a C program to check if a user-entered number is an Armstrong number (narcissistic number).
    **Expected Output:**
    ```
    Enter a number: 153
    153 is an Armstrong number.
    ```

69. **Question 69:**
    **Question:** Create a program that calculates the area of a triangle when the user provides the lengths of its three sides.
    **Expected Output:**
    ```
    Enter the lengths of three sides (separated by spaces): 5 12 13
    The area of the triangle is 30 square units.
    ```

70. **Question 70:**
    **Question:** Develop a C program to check if a user-entered number is a strong number.
    **Expected Output:**
    ```
    Enter a number: 145
    145 is a strong number.
    ```

71. **Question 71:**
    **Question:** Write a C program that checks if a user-entered number is a palindrome using a logical approach.
    **Expected Output:**
    ```
    Enter a number: 121
    121 is a palindrome.
    ```

72. **Question 72:**
    **Question:** Create a program that calculates the sum of squares of the first N even natural numbers.
    **Expected Output:**
    ```
    Enter the value of N: 4
    The sum of squares of the first 4 even natural numbers is 120.
    ```

73. **Question 73:**
    **Question:** Develop a C program that checks if a user-entered year is a leap year without using logical operators.
    **Expected Output:**
    ```
    Enter a year: 2024
    2024 is a leap year.
    ```

74. **Question 74:**
    **Question:** Write a program that calculates the sum of cubes of the first N odd natural numbers.
    **Expected Output:**
    ```
    Enter the value of N: 5
    The sum of cubes of the first 5 odd natural numbers is 135.
    ```

75. **Question 75:**
    **Question:** Create a C program that checks if a user-entered string is a pangram (contains all English alphabet letters).
    **Expected Output:**
    ```
    Enter a string: The quick brown fox jumps over the lazy dog.
    The string is a pangram.
    ```

76. **Question 76:**
    **Question:** Develop a program that calculates and displays the HCF (Highest Common Factor) of two user-entered numbers.
    **Expected Output:**
    ```
    Enter two numbers (separated by a space): 24 36
    The HCF of 24 and 36 is 12.
    ```

77. **Question 77:**
    **Question:** Write a C program that calculates the sum of the squares of prime numbers between 1 and 50.
    **Expected Output:**
    ```
    The sum of squares of prime numbers between 1 and 50 is 2418.
    ```

78. **Question 78:**
    **Question:** Create a program that checks if a user-entered number is an abundant number.
    **Expected Output:**
    ```
    Enter a number: 12
    12 is an abundant number.
    ```

79. **Question 79:**
    **Question:** Develop a C program that checks if a given string is a palindrome using pointers.
    **Expected Output:**
    ```
    Enter a string: racecar
    "racecar" is a palindrome.
    ```

80. **Question 80:**
    **Question:** Write a program that calculates the sum of digits of a user-entered number using a logical approach.
    **Expected Output:**
    ```
    Enter a number: 12345
    The sum of the digits is 15.
    ```

81. **Question 81:**
    **Question:** Create a C program to find and display the prime factors of a user-entered number.
    **Expected Output:**
    ```
    Enter a number: 60
    The prime factors of 60 are: 2 3 5
    ```

82. **Question 82:**
    **Question:** Develop a program that calculates the difference between the sum of squares and the square of the sum of the first N natural numbers.
    **Expected Output:**
    ```
    Enter the value of N: 5
    The difference is 170.
    ```

83. **Question 83:**
    **Question:** Write a C program that checks if a user-entered number is a strong number using logical operations.
    **Expected Output:**
    ```
    Enter a number: 145
    145 is a strong number.
    ```

84. **Question 84:**
    **Question:** Create a program that calculates and displays the LCM (Least Common Multiple) of three user-entered numbers.
    **Expected Output:**
    ```
    Enter three numbers (separated by spaces): 12 18 24
    The LCM of 12, 18, and 24 is 72.
    ```

85. **Question 85:**
    **Question:** Develop a C program that calculates the sum of natural numbers divisible by both 3 and 5 between 1 and 100.
    **Expected Output:**
    ```
    The sum of natural numbers divisible by both 3 and 5 between 1 and 100 is 315.
    ```

86. **Question 86:**
    **Question:** Write a program that checks if a user-entered number is a Kaprekar number.
    **Expected Output:**
    ```
    Enter a number: 9
    9 is a Kaprekar number.
    ```

87. **Question 87:**
    **Question:** Create a C program to find the sum of the series: 1 + 1/4 + 1/9 + 1/16 + ... + 1/n^2.
    **Expected Output:**
    ```
    Enter the value of n: 4
    The sum of the series is approximately 1.42361.
    ```

88. **Question 88:**
    **Question:** Develop a program that checks if a user-entered sentence is a palindrome (ignoring spaces and case).
    **Expected Output:**
    ```
    Enter a sentence: A man, a plan, a canal, Panama.
    The sentence is a palindrome.
    ```

89. **Question 89:**
    **Question:** Write a C program that calculates and displays the difference between the sum of even-indexed elements and odd-indexed elements in an array.
    **Expected Output:**
    ```
    Enter the number of elements in the array: 5
    Enter the elements (separated by spaces): 4 7 2 9 6
    The difference is 7.
    ```

90. **Question 90:**
    **Question:** Create a program that calculates the value of π using the Monte Carlo method for a user-specified number of iterations.
    **Expected Output:**
    ```
    Enter the number of iterations: 1000000
    The value of π is approximately 3.14159.
    ```

91. **Question 91:**
    **Question:** Write a C program that generates the first N prime numbers and displays them in a spiral pattern.
    **Expected Output:**
    ```
    Enter the value of N: 10
    Prime Numbers in a Spiral:
    17 16 15 14 13
    18  5  4  3 12
    19  6  1  2 11
    20  7  8  9 10
    21 22 23 24 25
    ```

92. **Question 92:**
    **Question:** Create a program that simulates a basic ATM machine. The user can withdraw, deposit, or check the balance.
    **Expected Output:** (Interaction example)
    ```
    Welcome to the ATM!
    Select an option:
    1. Withdraw
    2. Deposit
    3. Check Balance
    4. Exit
    Enter your choice: 1
    Enter the amount to withdraw: 100
    Successfully withdrawn $100. Current balance: $900
    ```

93. **Question 93:**
    **Question:** Develop a C program that simulates a simple tic-tac-toe game for two players.
    **Expected Output:** (Sample game interaction)
    ```
    Player 1, enter your move (row and column): 2 1
    Board after move:
    1 - -
    X - -
    - - -
    Player 2, enter your move (row and column): 1 2
    Board after move:
    1 O -
    X - -
    - - -
    ...
    ```

94. **Question 94:**
    **Question:** Write a C program to find and display the longest word in a user-entered sentence.
    **Expected Output:**
    ```
    Enter a sentence: The quick brown fox jumps over the lazy dog.
    The longest word in the sentence is "jumps".
    ```

95. **Question 95:**
    **Question:** Create a program that generates a random maze and finds a path from the start to the end point.
    **Expected Output:**
    ```
    Random Maze:
    # # # # # # # # # # #
    S       #   #       #
    # # #   # # #   # # #
    #   #   #       #   #
    #   # # #   # # # # #
    #   #           #   E
    # # # # # # # # # # #
    Path:
    S   * * * * * *   *
        *       #   * #
    # # #   # # #   # #
    #   #   #       # #
    #   # # #   # # # #
    #   #           # *
    # # # # # # # # # #
    ```

96. **Question 96:**
    **Question:** Develop a C program that simulates a simple Blackjack card game between the user and the computer.
    **Expected Output:** (Sample game interaction)
    ```
    Welcome to Blackjack!
    Player's Hand: 7 9
    Computer's Hand: 5 ?
    Do you want to hit or stand? (h/s): h
    Player's Hand: 7 9 Q
    ...
    ```

97. **Question 97:**
    **Question:** Write a program to calculate the sum of prime numbers in the Fibonacci sequence up to a user-entered limit.
    **Expected Output:**
    ```
    Enter the limit: 50
    The sum of prime Fibonacci numbers up to 50 is 104.
    ```

98. **Question 98:**
    **Question:** Create a C program that counts the number of occurrences of each word in a user-entered text document.
    **Expected Output:** (Sample input and output)
    ```
    Enter the text:
    This is a sample text. This is a sample document.
    Word Count:
    "This" occurs 2 times.
    "is" occurs 2 times.
    "a" occurs 2 times.
    "sample" occurs 2 times.
    "text." occurs 1 time.
    "document." occurs 1 time.
    ```

99. **Question 99:**
    **Question:** Develop a program that calculates and displays the sum of digits of factorial of a user-entered number.
    **Expected Output:**
    ```
    Enter a number: 5
    The sum of digits of 5! is 3.
    ```

100. **Question 100:**
    **Question:** Write a C program that generates and displays the first N numbers of the Lucas sequence.
    **Expected Output:**
    ```
    Enter the value of N: 8
    The first 8 Lucas numbers are: 2 1 3 4 7 11 18 29
    ```