What is an array in C programming?

An array in C programming is a collection of elements of the same data type stored at contiguous memory locations. Arrays allow you to store multiple values under a single variable name, making it easier to manage and manipulate data.

How do you declare an array in C?

To declare an array in C, specify the data type, array name, and size. For example, `int numbers[5];` declares an integer array named `numbers` with a size of 5.

How do you initialize an array in C?

You can initialize an array in C by providing a comma-separated list of values enclosed in braces. For example, `int numbers[5] = {1, 2, 3, 4, 5};` initializes the array `numbers` with the values 1, 2, 3, 4, and 5.

What is the difference between static and dynamic arrays in C?

Static arrays have a fixed size determined at compile time, while dynamic arrays can change size during runtime using pointers and memory allocation functions such as `malloc` and `free`.

How do you access elements of an array in C?

You access elements of an array in C using the array name followed by the index in square brackets. For example, `numbers[2]` accesses the third element of the array `numbers`.

Can you pass an array to a function in C?

Yes, you can pass an array to a function in C by specifying the array name without brackets. The function receives a pointer to the first element of the array, allowing it to access and modify the array elements.

What is a multi-dimensional array in C?

A multi-dimensional array in C is an array of arrays. The most common type is the two-dimensional array, which can be visualized as a matrix or table. For example, `int matrix[3][4];` declares a two-dimensional array with 3 rows and 4 columns.

How do you declare and initialize a two-dimensional array in C?

To declare a two-dimensional array in C, specify the data type, array name, and sizes of both dimensions. For example, `int matrix[3][4];` declares a 3x4 matrix. To initialize it, use nested braces: `int matrix[3][4] = {{1, 2, 3, 4}, {5, 6, 7, 8}, {9, 10, 11, 12}};`.

What are the limitations of arrays in C?

Arrays in C have fixed sizes, which must be known at compile time for static arrays. They also lack built-in bounds checking, which can lead to buffer overflows if you access elements outside the array's range.

How do you dynamically allocate memory for an array in C?

To dynamically allocate memory for an array in C, use the `malloc` or `calloc` functions. For example, `int *array = (int*)malloc(5 * sizeof(int));` allocates memory for an array of 5 integers.

How do you free dynamically allocated memory for an array in C?

To free dynamically allocated memory for an array in C, use the `free` function. For example, `free(array);` releases the memory allocated for the array.

What is pointer arithmetic, and how is it used with arrays in C?

Pointer arithmetic involves performing operations on pointers, such as addition or subtraction, to access different elements of an array. For example, `*(array + 1)` accesses the second element of the array `array`.

How can you iterate through an array using a for loop in C?

To iterate through an array using a for loop in C, use the loop to access each element by its index. For example: `for (int i = 0; i < 5; i++) { printf("%d\n", numbers[i]); }`.

What are jagged arrays, and does C support them?

Jagged arrays are arrays of arrays with different lengths. C does not directly support jagged arrays, but you can achieve similar functionality using arrays of pointers, with each pointer pointing to an array of different lengths.

How do you copy an array in C?

To copy an array in C, use a loop to copy each element from the source array to the destination array. For example: `for (int i = 0; i < size; i++) { dest[i] = src[i]; }`.

Can you use the `sizeof` operator with arrays in C?

Yes, you can use the `sizeof` operator with arrays in C to determine the total size in bytes. For example, `sizeof(array)` returns the size of the entire array, while `sizeof(array[0])` returns the size of one element.

How do you find the length of an array in C?

To find the length of an array in C, divide the total size of the array by the size of one element: `int length = sizeof(array) / sizeof(array[0]);`.

What is an array of strings in C?

An array of strings in C is a two-dimensional array of characters, where each row represents a string. For example: `char names[3][10] = {"Alice", "Bob", "Charlie"};` declares an array of 3 strings, each with a maximum length of 9 characters plus a null terminator.

What are some common mistakes to avoid when working with arrays in C?

Common mistakes when working with arrays in C include accessing out-of-bounds elements, forgetting to free dynamically allocated memory, and using incorrect array sizes. Ensuring proper bounds checking and memory management can help avoid these issues.

How do you reverse an array in C?

To reverse an array in C, swap the elements from both ends moving towards the center. For example: `for (int i = 0; i < size / 2; i++) { int temp = array[i]; array[i] = array[size - 1 - i]; array[size - 1 - i] = temp; }`.

Arrays MCQs - Part 1 » 📚 Challenge Yourself With These MCQs

Home » Programming Languages » C Programming » Arrays MCQs » Part 1 » 100 Questions

Timer: Off

Random: Off

1. What is an array in C?

ⓐ. A single variable that holds multiple values of different types

ⓑ. A data structure that can hold multiple values of the same type

ⓒ. A function that can return multiple values

ⓓ. A collection of strings

Correct Answer: A data structure that can hold multiple values of the same type

Explanation: An array in C is a data structure that can store a fixed-size sequence of elements of the same data type.

2. How do you declare an integer array of size 10 in C?

ⓐ. int array[10];

ⓑ. int array{10};

ⓒ. int array(10);

ⓓ. int array<10>;

Correct Answer: int array[10];

Explanation: The correct syntax to declare an integer array of size 10 in C is `int array[10];`.

3. Which of the following correctly initializes all elements of an integer array to zero in C?

ⓐ. int array[5] = {0};

ⓑ. int array[5] = {0, 0, 0, 0, 0};

ⓒ. int array[5] = {0, 0, 0, 0};

ⓓ. All of the above

Correct Answer: All of the above

Explanation: In C, an array can be initialized to zero using any of these methods. If only one zero is provided, the remaining elements are automatically initialized to zero.

4. What is the index of the first element in a C array?

ⓐ. -1

ⓑ. 0

ⓒ. 1

ⓓ. 2

Correct Answer: 0

Explanation: In C, the indexing of array elements starts from 0, so the first element is at index 0.

5. Which statement correctly accesses the third element in an array named `numbers`?

ⓐ. numbers[3];

ⓑ. numbers(3);

ⓒ. numbers[2];

ⓓ. numbers{2};

Correct Answer: numbers[2];

Explanation: Arrays in C are zero-indexed, so the third element is accessed with index 2.

6. What will be the output of the following code?


#include <stdio.h>
int array[5] = {1, 2, 3, 4, 5};
printf("%d", array[2]);

ⓐ. 1

ⓑ. 2

ⓒ. 3

ⓓ. 4

Correct Answer: 3

Explanation: The array `array` has its elements indexed from 0 to 4. `array[2]` refers to the third element, which is 3.

7. How do you define a two-dimensional array of integers in C?

ⓐ. int array[3, 4];

ⓑ. int array[3][4];

ⓒ. int array{3}{4};

ⓓ. int array(3, 4);

Correct Answer: int array[3][4];

Explanation: The correct syntax to define a two-dimensional array of integers in C is `int array[3][4];`.

8. Which of the following correctly accesses the element in the second row and third column of a two-dimensional array `matrix`?

ⓐ. matrix[1][2];

ⓑ. matrix[2][3];

ⓒ. matrix[2][2];

ⓓ. matrix[1][3];

Correct Answer: matrix[1][2];

Explanation: In a two-dimensional array, the first index is the row, and the second index is the column. Since indexing starts from 0, `matrix[1][2]` accesses the second row and third column.

9. What will be the result of the following code?


#include <stdio.h>
int arr[4] = {10, 20, 30, 40};
int sum = 0;
for(int i = 0; i < 4; i++) {
    sum += arr[i];
}
printf("%d", sum);

ⓐ. 100

ⓑ. 90

ⓒ. 80

ⓓ. 70

Correct Answer: 100

Explanation: The code sums up all elements of the array `arr`, resulting in 10 + 20 + 30 + 40 = 100.

10. What does the following declaration represent?


#include <stdio.h>
int arr[][3] = {{1, 2, 3}, {4, 5, 6}};

ⓐ. A one-dimensional array of 6 integers

ⓑ. A two-dimensional array with 2 rows and 3 columns

ⓒ. A three-dimensional array

ⓓ. An array of pointers

Correct Answer: A two-dimensional array with 2 rows and 3 columns

Explanation: This declaration defines a two-dimensional array with 2 rows and 3 columns, where the elements are specified in the initialization list.

11. What is the size of the following array in bytes, assuming an integer is 4 bytes?


#include <stdio.h>
int arr[10];

ⓐ. 10 bytes

ⓑ. 20 bytes

ⓒ. 40 bytes

ⓓ. 80 bytes

Correct Answer: 40 bytes

Explanation: The size of the array `arr` is 10 integers, and each integer is 4 bytes. Therefore, the total size is 10 * 4 = 40 bytes.

12. Which of the following statements correctly initializes an array of 5 integers?

ⓐ. int arr[] = {1, 2, 3, 4, 5};

ⓑ. int arr[5] = {1, 2, 3, 4, 5};

ⓒ. int arr[5] = {1, 2, 3};

ⓓ. All of the above

Correct Answer: All of the above

Explanation: All the given options correctly initialize an array. The first and second explicitly specify the size, while the third initializes the first three elements and the rest are initialized to zero.

13. Which function can be used to find the size of an array in C?

ⓐ. size()

ⓑ. length()

ⓒ. sizeof()

ⓓ. array_size()

Correct Answer: sizeof()

Explanation: The `sizeof()` operator in C is used to determine the size of a variable or an array in bytes.

14. What will be the output of the following code?


#include <stdio.h>
int arr[3] = {10, 20, 30};
printf("%d", arr[3]);

ⓐ. 10

ⓑ. 20

ⓒ. 30

ⓓ. Undefined behavior

Correct Answer: Undefined behavior

Explanation: Accessing `arr[3]` is out of bounds since the valid indices for `arr` are 0, 1, and 2. This results in undefined behavior.

15. Which of the following correctly assigns the value 50 to the last element of an integer array `arr` of size 5?

ⓐ. arr[4] = 50;

ⓑ. arr[5] = 50;

ⓒ. arr[6] = 50;

ⓓ. arr[-1] = 50;

Correct Answer: arr[4] = 50;

Explanation: In a zero-indexed array of size 5, the last element is at index 4. Thus, `arr[4] = 50;` correctly assigns the value 50 to the last element.

16. How can you initialize an array `arr` of size 5 with all elements set to zero?

ⓐ. int arr[5] = {0, 0, 0, 0, 0};

ⓑ. int arr[5] = {0};

ⓒ. memset(arr, 0, 5 * sizeof(int));

ⓓ. All of the above

Correct Answer: All of the above

Explanation: All these methods correctly initialize an array of size 5 with all elements set to zero.

17. What will be the output of the following code?


#include <stdio.h>
int arr[] = {5, 10, 15, 20};
printf("%d", arr[1] + arr[3]);

ⓐ. 15

ⓑ. 25

ⓒ. 30

ⓓ. 35

Correct Answer: 30

Explanation: `arr[1]` is 10 and `arr[3]` is 20. The sum is 10 + 20 = 30.

18. Which of the following best describes how arrays are passed to functions in C?

ⓐ. By value

ⓑ. By reference

ⓒ. By copying the array

ⓓ. By value, but only the first element

Correct Answer: By reference

Explanation: In C, arrays are passed to functions by reference, meaning the address of the first element is passed, not the entire array.

19. What will be the output of the following code?


#include <stdio.h>
int arr[] = {1, 2, 3, 4, 5};
int *p = arr;
printf("%d", *(p + 2));

ⓐ. 1

ⓑ. 2

ⓒ. 3

ⓓ. 4

Correct Answer: 3

Explanation: `p` points to the first element of `arr`. `*(p + 2)` dereferences the pointer to the third element, which is 3.

20. What does the following declaration represent?


#include <stdio.h>
int arr[5] = {0};

ⓐ. An array of 5 integers, all initialized to zero

ⓑ. An array of 5 integers with the first element initialized to zero

ⓒ. An array of 1 integer initialized to zero

ⓓ. An array of 5 integers with undefined values

Correct Answer: An array of 5 integers, all initialized to zero

Explanation: The declaration initializes an array of 5 integers, where all elements are set to zero because only the first element is explicitly initialized, and the rest are implicitly set to zero.

21. How do you declare a two-dimensional array of integers with 3 rows and 4 columns in C?

ⓐ. int arr[3, 4];

ⓑ. int arr[3][4];

ⓒ. int arr[4][3];

ⓓ. int arr[3]{4};

Correct Answer: int arr[3][4];

Explanation: The correct syntax to declare a two-dimensional array of integers with 3 rows and 4 columns in C is `int arr[3][4];`.

22. Which of the following statements initializes all elements of a 3x3 two-dimensional array to zero?

ⓐ. int arr[3][3] = {0};

ⓑ. int arr[3][3] = {0, 0, 0, 0, 0, 0, 0, 0, 0};

ⓒ. int arr[3][3] = {{0, 0, 0}, {0, 0, 0}, {0, 0, 0}};

ⓓ. All of the above

Correct Answer: All of the above

Explanation: Each of these statements initializes all elements of a 3x3 two-dimensional array to zero.

23. How do you access the element in the second row and third column of a two-dimensional array `arr`?

ⓐ. arr[2][3]

ⓑ. arr[3][2]

ⓒ. arr[1][2]

ⓓ. arr[2][1]

Correct Answer: arr[1][2]

Explanation: Since array indexing starts at 0, `arr[1][2]` accesses the element in the second row and third column.

24. What will be the output of the following code?


#include <stdio.h>
int arr[2][3] = {{1, 2, 3}, {4, 5, 6}};
printf("%d", arr[1][1]);

ⓐ. 1

ⓑ. 2

ⓒ. 4

ⓓ. 5

Correct Answer: 5

Explanation: `arr[1][1]` accesses the element in the second row and second column, which is 5.

25. Which of the following correctly initializes a 2x2 two-dimensional array with the elements 1, 2, 3, and 4?

ⓐ. int arr[2][2] = {1, 2, 3, 4};

ⓑ. int arr[2][2] = {{1, 2}, {3, 4}};

ⓒ. int arr[2][2] = {1, 2, {3, 4}};

ⓓ. int arr[2][2] = {{1, 2, 3, 4}};

Correct Answer: int arr[2][2] = {{1, 2}, {3, 4}};

Explanation: The correct way to initialize a 2x2 array with these elements is to use nested curly braces to separate the rows.

26. What will be the result of the following code?


#include <stdio.h>
int arr[3][3] = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}};
int sum = 0;
for(int i = 0; i < 3; i++) {
    sum += arr[i][i];
}
printf("%d", sum);

ⓐ. 15

ⓑ. 18

ⓒ. 21

ⓓ. 24

Correct Answer: 15

Explanation: The code sums the diagonal elements of the array: 1 + 5 + 9 = 15.

27. Which statement correctly assigns the value 10 to the element in the first row and second column of a two-dimensional array `arr`?

ⓐ. arr[0][1] = 10;

ⓑ. arr[1][0] = 10;

ⓒ. arr[1][1] = 10;

ⓓ. arr[0][2] = 10;

Correct Answer: arr[0][1] = 10;

Explanation: In a zero-indexed two-dimensional array, `arr[0][1]` refers to the first row and second column.

28. How can you iterate through all elements of a 2x2 two-dimensional array `arr`?

ⓐ.


#include <stdio.h>
for(int i = 0; i < 2; i++)
    for(int j = 0; j < 2; j++)
        // Access arr[i][j]

ⓑ.


#include <stdio.h>
for(int i = 0; i < 2; i++)
    // Access arr[i][i]

ⓒ.


#include <stdio.h>
for(int j = 0; j < 2; j++)
    // Access arr[j][j]

ⓓ.


#include <stdio.h>
for(int i = 0; i < 2; i++)
    for(int j = 0; j < 2; j++)
        // Access arr[j][i]

Correct Answer:


#include <stdio.h>
for(int i = 0; i < 2; i++)
    for(int j = 0; j < 2; j++)
        // Access arr[i][j]

Explanation: To iterate through all elements of a 2x2 array, you need nested loops where the outer loop iterates over rows and the inner loop iterates over columns.

29. What will be the output of the following code?


#include <stdio.h>
int arr[2][2] = {{1, 2}, {3, 4}};
printf("%d", arr[0][0] + arr[1][1]);

ⓐ. 2

ⓑ. 3

ⓒ. 4

ⓓ. 5

Correct Answer: 5

Explanation: `arr[0][0]` is 1 and `arr[1][1]` is 4. The sum is 1 + 4 = 5.

30. Which of the following best describes the memory layout of a two-dimensional array in C?

ⓐ. The elements are stored in a single contiguous block of memory, row-wise.

ⓑ. The elements are stored in a single contiguous block of memory, column-wise.

ⓒ. The elements are stored in separate blocks for each row.

ⓓ. The elements are stored in separate blocks for each column.

Correct Answer: The elements are stored in a single contiguous block of memory, row-wise.

Explanation: In C, a two-dimensional array is stored in a single contiguous block of memory, with elements laid out row-wise.

31. How do you declare a three-dimensional array of integers with dimensions 2x3x4 in C?

ⓐ. int arr[2][3][4];

ⓑ. int arr[2][3][4][4];

ⓒ. int arr[3][2][4];

ⓓ. int arr[4][3][2];

Correct Answer: int arr[2][3][4];

Explanation: The correct syntax to declare a three-dimensional array of integers with dimensions 2x3x4 in C is `int arr[2][3][4];`.

32. Which of the following correctly initializes a 2x2x2 three-dimensional array with all elements set to 1?

ⓐ. int arr[2][2][2] = {1};

ⓑ. int arr[2][2][2] = {{{1}, {1}}, {{1}, {1}}};

ⓒ. int arr[2][2][2] = {{{1, 1}, {1, 1}}, {{1, 1}, {1, 1}}};

ⓓ. int arr[2][2][2] = {1, 1, 1, 1, 1, 1, 1, 1};

Correct Answer: int arr[2][2][2] = {{{1, 1}, {1, 1}}, {{1, 1}, {1, 1}}};

Explanation: The correct way to initialize a 2x2x2 three-dimensional array with all elements set to 1 is to use nested curly braces for each dimension.

33. How do you access the element in the first row, second column, and third depth of a three-dimensional array `arr`?

ⓐ. arr[1][2][3]

ⓑ. arr[0][1][2]

ⓒ. arr[1][1][2]

ⓓ. arr[0][2][1]

Correct Answer: arr[0][1][2]

Explanation: In a zero-indexed three-dimensional array, `arr[0][1][2]` accesses the element in the first row, second column, and third depth.

34. What will be the output of the following code?


#include <stdio.h>
int arr[2][2][2] = {{{1, 2}, {3, 4}}, {{5, 6}, {7, 8}}};
printf("%d", arr[1][0][1]);

ⓐ. 2

ⓑ. 4

ⓒ. 5

ⓓ. 6

Correct Answer: 6

Explanation: `arr[1][0][1]` accesses the element in the second row, first column, and second depth, which is 6.

35. Which of the following correctly sums all elements in a 2x2x2 three-dimensional array `arr`?

ⓐ.


#include <stdio.h>
int sum = 0;
for(int i = 0; i < 2; i++)
    for(int j = 0; j < 2; j++)
        for(int k = 0; k < 2; k++)
            sum += arr[i][j][k];

ⓑ.


#include <stdio.h>
int sum = 0;
for(int i = 0; i < 2; i++)
    for(int j = 0; j < 2; j++)
        sum += arr[i][j];

ⓒ.


#include <stdio.h>
int sum = 0;
for(int i = 0; i < 2; i++)
    sum += arr[i];

ⓓ.


#include <stdio.h>
int sum = 0;
for(int i = 0; i < 2; i++)
    for(int j = 0; j < 2; j++)
        for(int k = 0; k < 2; k++)
            sum += arr[j][i][k];

Correct Answer:


#include <stdio.h>
int sum = 0;
for(int i = 0; i < 2; i++)
    for(int j = 0; j < 2; j++)
        for(int k = 0; k < 2; k++)
            sum += arr[i][j][k];

Explanation: To sum all elements in a 2x2x2 three-dimensional array, nested loops are needed for each dimension.

36. What is the memory layout of a multidimensional array in C?

ⓐ. Contiguous block of memory, row-major order

ⓑ. Contiguous block of memory, column-major order

ⓒ. Separate blocks for each dimension

ⓓ. Mixed block and contiguous memory

Correct Answer: Contiguous block of memory, row-major order

Explanation: In C, multidimensional arrays are stored in a single contiguous block of memory in row-major order, meaning the rightmost index varies the fastest.

37. How can you determine the number of elements in a three-dimensional array `arr` defined as `int arr[3][4][2];`?

ⓐ. sizeof(arr)

ⓑ. sizeof(arr) / sizeof(int)

ⓒ. sizeof(arr) / sizeof(arr[0][0][0])

ⓓ. sizeof(arr) / sizeof(arr[0])

Correct Answer: sizeof(arr) / sizeof(arr[0][0][0])

Explanation: The total number of elements in the array is the total size divided by the size of one element. `sizeof(arr) / sizeof(arr[0][0][0])` gives the number of elements.

38. What will be the output of the following code?


#include <stdio.h>
int arr[2][2][2] = {{{1, 2}, {3, 4}}, {{5, 6}, {7, 8}}};
printf("%d", arr[0][1][1] + arr[1][1][0]);

ⓐ. 8

ⓑ. 9

ⓒ. 10

ⓓ. 11

Correct Answer: 10

Explanation: `arr[0][1][1]` is 4 and `arr[1][1][0]` is 7. The sum is 4 + 7 = 11.

39. Which of the following correctly assigns the value 9 to the element in the second row, first column, and first depth of a three-dimensional array `arr`?

ⓐ. arr[1][0][0] = 9;

ⓑ. arr[0][1][0] = 9;

ⓒ. arr[0][0][1] = 9;

ⓓ. arr[1][1][0] = 9;

Correct Answer: arr[1][0][0] = 9;

Explanation: In a zero-indexed three-dimensional array, `arr[1][0][0]` refers to the second row, first column, and first depth.

40. How do you define a four-dimensional array of integers with dimensions 2x2x2x2 in C?

ⓐ. int arr[2][2][2][2];

ⓑ. int arr[4][4];

ⓒ. int arr[2][2][2];

ⓓ. int arr[16];

Correct Answer: int arr[2][2][2][2];

Explanation: The correct syntax to declare a four-dimensional array of integers with dimensions 2x2x2x2 in C is `int arr[2][2][2][2];`.

41. Which of the following correctly initializes an array of 5 integers with values 1, 2, 3, 4, and 5?

ⓐ. int arr[5] = {1, 2, 3, 4, 5};

ⓑ. int arr[5] = 1, 2, 3, 4, 5;

ⓒ. int arr[5] = {1; 2; 3; 4; 5};

ⓓ. int arr[5] = (1, 2, 3, 4, 5);

Correct Answer: int arr[5] = {1, 2, 3, 4, 5};

Explanation: The correct syntax to initialize an array of 5 integers with these values is `int arr[5] = {1, 2, 3, 4, 5};`.

42. What will be the contents of the array `arr` after the following code executes?


#include <stdio.h>
int arr[5] = {1, 2};

ⓐ. {1, 2, 0, 0, 0}

ⓑ. {1, 2, 2, 2, 2}

ⓒ. {1, 2, 1, 2, 1}

ⓓ. {0, 0, 0, 0, 0}

Correct Answer: {1, 2, 0, 0, 0}

Explanation: When an array is partially initialized, the remaining elements are set to zero.

43. How do you initialize all elements of an integer array `arr` of size 10 to zero?

ⓐ. int arr[10] = {0};

ⓑ. int arr[10] = 0;

ⓒ. int arr[10] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0};

ⓓ. Both A and C

Correct Answer: Both A and C

Explanation: Both `int arr[10] = {0};` and `int arr[10] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0};` correctly initialize all elements to zero.

44. Which of the following correctly initializes a two-dimensional array with the first row as {1, 2, 3} and the second row as {4, 5, 6}?

ⓐ. int arr[2][3] = {1, 2, 3, 4, 5, 6};

ⓑ. int arr[2][3] = {{1, 2, 3}, {4, 5, 6}};

ⓒ. int arr[2][3] = {(1, 2, 3), (4, 5, 6)};

ⓓ. int arr[2][3] = {[1] = {4, 5, 6}, [0] = {1, 2, 3}};

Correct Answer: int arr[2][3] = {{1, 2, 3}, {4, 5, 6}};

Explanation: The correct syntax to initialize a two-dimensional array with these values is `int arr[2][3] = {{1, 2, 3}, {4, 5, 6}};`.

45. What will be the contents of the array `arr` after the following code executes?


#include <stdio.h>
int arr[4] = {0, 1, [3] = 3};

ⓐ. {0, 1, 0, 3}

ⓑ. {0, 1, 3, 0}

ⓒ. {0, 1, 1, 3}

ⓓ. {0, 1, 3, 3}

Correct Answer: {0, 1, 0, 3}

Explanation: This code uses designated initializers. The value at index 3 is explicitly set to 3, and the unspecified element at index 2 is initialized to 0.

46. How can you initialize a character array `str` with the string "Hello"?

ⓐ. char str[] = {'H', 'e', 'l', 'l', 'o', '\0'};

ⓑ. char str[] = "Hello";

ⓒ. char str[6] = "Hello";

ⓓ. All of the above

Correct Answer: All of the above

Explanation: All these methods correctly initialize a character array with the string "Hello". Option A uses a character array with a null terminator, while B and C use string literals which automatically add the null terminator.

47. Which of the following statements about array initialization is true?

ⓐ. An array must be fully initialized at the time of declaration.

ⓑ. An array cannot be partially initialized.

ⓒ. If an array is partially initialized, the remaining elements are automatically initialized to zero.

ⓓ. If an array is partially initialized, the remaining elements contain garbage values.

Correct Answer: If an array is partially initialized, the remaining elements are automatically initialized to zero.

Explanation: In C, if an array is partially initialized, the unspecified elements are automatically initialized to zero.

48. What will be the output of the following code?


#include <stdio.h>
int arr[3] = {1, 2};
printf("%d", arr[2]);

ⓐ. 0

ⓑ. 1

ⓒ. 2

ⓓ. Undefined behavior

Correct Answer: 0

Explanation: Since the array is partially initialized, the third element `arr[2]` is automatically set to 0.

49. How do you initialize a float array `arr` of size 4 with values 1.1, 2.2, 3.3, and 4.4?

ⓐ. float arr[4] = {1.1, 2.2, 3.3, 4.4};

ⓑ. float arr[4] = {1, 2, 3, 4};

ⓒ. float arr[4] = 1.1, 2.2, 3.3, 4.4;

ⓓ. float arr[4] = {1.1f, 2.2f, 3.3f, 4.4f};

Correct Answer: float arr[4] = {1.1, 2.2, 3.3, 4.4};

Explanation: The correct syntax to initialize a float array with these values is `float arr[4] = {1.1, 2.2, 3.3, 4.4};`.

50. What will be the result of the following code?


#include <stdio.h>
int arr[5] = {[2] = 5, [4] = 10};
printf("%d %d %d %d %d", arr[0], arr[1], arr[2], arr[3], arr[4]);

ⓐ. 0 0 5 0 10

ⓑ. 0 5 0 10 0

ⓒ. 5 0 0 10 0

ⓓ. 5 10 0 0 0

Correct Answer: 0 0 5 0 10

Explanation: The code uses designated initializers to set `arr[2]` to 5 and `arr[4]` to 10. The remaining elements are initialized to 0.

51. How do you insert an element into an array at a specific position in C?

ⓐ. Overwrite the element at the specified position

ⓑ. Shift the elements from the specified position to the right

ⓒ. Shift the elements from the specified position to the left

ⓓ. Create a new array with the inserted element

Correct Answer: Shift the elements from the specified position to the right

Explanation: To insert an element into an array at a specific position, you need to shift the elements from that position to the right to make space for the new element.

52. Which of the following is the correct way to traverse an array in C?

ⓐ. Using a while loop

ⓑ. Using a do-while loop

ⓒ. Using a for loop

ⓓ. All of the above

Correct Answer: All of the above

Explanation: You can traverse an array using any of these loops: while loop, do-while loop, or for loop.

53. What is the time complexity of inserting an element at the beginning of an array?

ⓐ. O(1)

ⓑ. O(n)

ⓒ. O(log n)

ⓓ. O(n^2)

Correct Answer: O(n)

Explanation: Inserting an element at the beginning of an array requires shifting all existing elements to the right, which takes O(n) time.

54. How do you delete an element from an array at a specific position in C?

ⓐ. Overwrite the element with zero

ⓑ. Shift the elements from the specified position to the left

ⓒ. Shift the elements from the specified position to the right

ⓓ. Create a new array without the deleted element

Correct Answer: Shift the elements from the specified position to the left

Explanation: To delete an element from an array at a specific position, you need to shift the elements from that position to the left to fill the gap.

55. What will be the output of the following code?


#include <stdio.h>
int arr[5] = {1, 2, 3, 4, 5};
for (int i = 0; i < 5; i++) {
    printf("%d ", arr[i]);
}

ⓐ. 1 2 3 4 5

ⓑ. 1 2 3 4 5 6

ⓒ. 5 4 3 2 1

ⓓ. 0 1 2 3 4

Correct Answer: 1 2 3 4 5

Explanation: The code traverses the array and prints each element, resulting in the output "1 2 3 4 5".

56. What is the time complexity of deleting an element from the end of an array?

ⓐ. O(1)

ⓑ. O(n)

ⓒ. O(log n)

ⓓ. O(n^2)

Correct Answer: O(1)

Explanation: Deleting an element from the end of an array is a constant time operation, O(1), since no elements need to be shifted.

57. What will be the contents of the array `arr` after the following code executes?


#include <stdio.h>
int arr[5] = {1, 2, 3, 4, 5};
for (int i = 3; i < 5; i++) {
    arr[i - 1] = arr[i];
}

ⓐ. {1, 2, 3, 5, 5}

ⓑ. {1, 2, 4, 5, 5}

ⓒ. {1, 2, 4, 5}

ⓓ. {1, 2, 3, 4}

Correct Answer: {1, 2, 3, 5, 5}

Explanation: The code shifts elements starting from index 3 to the left, resulting in `arr[2] = 4` and `arr[3] = 5`.

58. Which of the following statements correctly inserts an element `x` into an array `arr` at position `pos`?

ⓐ.


#include <stdio.h>
for (int i = n; i > pos; i--) {
    arr[i] = arr[i - 1];
}
arr[pos] = x;

ⓑ.


#include <stdio.h>
for (int i = n - 1; i >= pos; i--) {
    arr[i] = arr[i - 1];
}
arr[pos] = x;

ⓒ.


#include <stdio.h>
for (int i = n - 1; i >= pos; i--) {
    arr[i + 1] = arr[i];
}
arr[pos] = x;

ⓓ.


#include <stdio.h>
for (int i = pos; i < n; i++) {
    arr[i + 1] = arr[i];
}
arr[pos] = x;

Correct Answer:


#include <stdio.h>
for (int i = n - 1; i >= pos; i--) {
    arr[i + 1] = arr[i];
}
arr[pos] = x;

Explanation: This code shifts elements to the right starting from the end of the array, making space for the new element at position `pos`.

59. What is the time complexity of traversing an array of size `n`?

ⓐ. O(1)

ⓑ. O(n)

ⓒ. O(log n)

ⓓ. O(n^2)

Correct Answer: O(n)

Explanation: Traversing an array requires visiting each element once, resulting in a time complexity of O(n).

60. How do you replace the element at the third position in an array with a new value `x`?

ⓐ. arr[2] = x;

ⓑ. arr[3] = x;

ⓒ. arr[1] = x;

ⓓ. arr[4] = x;

Correct Answer: arr[2] = x;

Explanation: Array indexing starts at 0, so the third position corresponds to index 2.

61. What will be the output of the following code?


#include <stdio.h>
int arr[6] = {1, 2, 3, 4, 5, 6};
for (int i = 0; i < 6; i += 2) {
    printf("%d ", arr[i]);
}

ⓐ. 1 2 3 4 5 6

ⓑ. 2 4 6

ⓒ. 1 3 5

ⓓ. 1 3 5 7

Correct Answer: 1 3 5

Explanation: The loop increments `i` by 2 each time, so it prints the elements at even indices: 1, 3, and 5.

62. What will be the contents of the array `arr` after the following code executes?


#include <stdio.h>
int arr[6] = {1, 2, 3, 4, 5, 6};
for (int i = 1; i < 6; i++) {
    arr[i - 1] = arr[i];
}

ⓐ. {1, 2, 3, 4, 5, 6}

ⓑ. {2, 3, 4, 5, 6, 6}

ⓒ. {1, 1, 1, 1, 1, 1}

ⓓ. {2, 3, 4, 5, 6}

Correct Answer: {2, 3, 4, 5, 6, 6}

Explanation: The loop shifts elements to the left starting from index 1, resulting in `arr[5]` being duplicated.

63. Which of the following correctly removes an element from an array `arr` at position `pos`?

ⓐ.


#include <stdio.h>
for (int i = pos; i < n; i++) {
    arr[i] = arr[i + 1];
}

ⓑ.


#include <stdio.h>
for (int i = pos; i < n - 1; i++) {
    arr[i] = arr[i + 1];
}

ⓒ.


#include <stdio.h>
for (int i = pos; i < n - 1; i++) {
    arr[i + 1] = arr[i];
}

ⓓ.


#include <stdio.h>
for (int i = pos; i < n; i++) {
    arr[i + 1] = arr[i];
}

Correct Answer:


#include <stdio.h>
for (int i = pos; i < n - 1; i++) {
    arr[i] = arr[i + 1];
}

Explanation: This code shifts elements to the left starting from position `pos`, effectively removing the element at that position.

64. What is the time complexity of deleting an element from the beginning of an array?

ⓐ. O(1)

ⓑ. O(n)

ⓒ. O(log n)

ⓓ. O(n^2)

Correct Answer: O(n)

Explanation: Deleting an element from the beginning of an array requires shifting all subsequent elements to the left, which takes O(n) time.

65. What will be the output of the following code?


#include <stdio.h>
int arr[5] = {1, 2, 3, 4, 5};
for (int i = 4; i >= 0; i--) {
    printf("%d ", arr[i]);
}

ⓐ. 5 4 3 2 1

ⓑ. 1 2 3 4 5

ⓒ. 5 4 3 2 1 0

ⓓ. 0 1 2 3 4 5

Correct Answer: 5 4 3 2 1

Explanation: The loop traverses the array in reverse order, printing each element.

66. What is the primary purpose of array traversal?

ⓐ. Inserting elements into the array

ⓑ. Deleting elements from the array

ⓒ. Accessing and processing each element in the array

ⓓ. Sorting the array

Correct Answer: Accessing and processing each element in the array

Explanation: Array traversal is used to access and process each element in the array.

67. What will be the contents of the array `arr` after the following code executes?


#include <stdio.h>
int arr[6] = {1, 2, 3, 4, 5, 6};
int pos = 3;
int x = 10;
for (int i = 5; i >= pos; i--) {
    arr[i + 1] = arr[i];
}
arr[pos] = x;

ⓐ. {1, 2, 3, 10, 4, 5, 6}

ⓑ. {1, 2, 3, 4, 10, 5, 6}

ⓒ. {1, 2, 3, 4, 5, 10, 6}

ⓓ. {1, 2, 3, 4, 5, 6, 10}

Correct Answer: {1, 2, 3, 4, 10, 5, 6}

Explanation: The code shifts elements to the right starting from index 5 to make space for the new element `x` at position 3.

68. What is the time complexity of inserting an element into a sorted array while maintaining the sorted order?

ⓐ. O(1)

ⓑ. O(n)

ⓒ. O(log n)

ⓓ. O(n^2)

Correct Answer: O(n)

Explanation: Inserting an element into a sorted array requires finding the correct position (O(log n)) and then shifting elements to make space (O(n)), resulting in an overall complexity of O(n).

69. How do you traverse an array and print its elements in reverse order?

ⓐ.


#include <stdio.h>
for (int i = n - 1; i >= 0; i--) {
    printf("%d ", arr[i]);
}

ⓑ.


#include <stdio.h>
for (int i = 0; i < n; i++) {
    printf("%d ", arr[n - i - 1]);
}

ⓒ. Both A and B

ⓓ. Neither A nor B

Correct Answer: Both A and B

Explanation: Both methods correctly traverse the array in reverse order and print each element.

70. Which of the following correctly removes the first occurrence of a value `x` from an array `arr`?

ⓐ.


#include <stdio.h>
int pos;
for (pos = 0; pos < n; pos++) {
    if (arr[pos] == x) break;
}
for (int i = pos; i < n - 1; i++) {
    arr[i] = arr[i + 1];
}

ⓑ.


#include <stdio.h>
int pos;
for (pos = 0; pos < n; pos++) {
    if (arr[pos] == x) break;
}
for (int i = pos + 1; i < n; i++) {
    arr[i - 1] = arr[i];
}

ⓒ. Both A and B

ⓓ. Neither A nor B

Correct Answer: Both A and B

Explanation: Both methods correctly find the first occurrence of `x` and shift elements to the left to remove it.

71. What will be the contents of the array `arr` after the following code executes?


#include <stdio.h>
int arr[5] = {1, 2, 3, 4, 5};
int x = 3;
int pos;
for (pos = 0; pos < 5; pos++) {
    if (arr[pos] == x) break;
}
for (int i = pos; i < 4; i++) {
    arr[i] = arr[i + 1];
}

ⓐ. {1, 2, 3, 4, 5}

ⓑ. {1, 2, 4, 5, 5}

ⓒ. {1, 2, 3, 5, 5}

ⓓ. {1, 2, 4, 5}

Correct Answer: {1, 2, 4, 5, 5}

Explanation: The code finds the first occurrence of `x` and shifts elements to the left, but doesn't handle the last element properly.

72. What is the time complexity of traversing a two-dimensional array of size `m x n`?

ⓐ. O(m + n)

ⓑ. O(m * n)

ⓒ. O(m log n)

ⓓ. O(m^2 + n^2)

Correct Answer: O(m * n)

Explanation: Traversing a two-dimensional array requires visiting each element once, resulting in a time complexity of O(m * n).

73. What will be the output of the following code?


#include <stdio.h>
int arr[4] = {1, 2, 3, 4};
for (int i = 0; i < 4; i++) {
    printf("%d ", arr[3 - i]);
}

ⓐ. 4 3 2 1

ⓑ. 1 2 3 4

ⓒ. 1 3 2 4

ⓓ. 4 2 3 1

Correct Answer: 4 3 2 1

Explanation: The loop prints the elements in reverse order.

74. Which of the following correctly finds and prints the maximum value in an array `arr` of size `n`?

ⓐ.


#include <stdio.h>
int max = arr[0];
for (int i = 1; i < n; i++) {
    if (arr[i] > max) max = arr[i];
}
printf("%d", max);

ⓑ.


#include <stdio.h>
int max = arr[0];
for (int i = 0; i < n; i++) {
    if (arr[i] > max) max = arr[i];
}
printf("%d", max);

ⓒ.


#include <stdio.h>
int max = arr[1];
for (int i = 1; i < n; i++) {
    if (arr[i] > max) max = arr[i];
}
printf("%d", max);

ⓓ.


#include <stdio.h>
int max = arr[0];
for (int i = 1; i <= n; i++) {
    if (arr[i] > max) max = arr[i];
}
printf("%d", max);

Correct Answer:


#include <stdio.h>
int max = arr[0];
for (int i = 1; i < n; i++) {
    if (arr[i] > max) max = arr[i];
}
printf("%d", max);

Explanation: This code correctly initializes `max` to the first element and updates it by comparing with each element in the array.

75. What will be the output of the following code?


#include <stdio.h>
int arr[4] = {1, 2, 3, 4};
int sum = 0;
for (int i = 0; i < 4; i++) {
    sum += arr[i];
}
printf("%d", sum);

ⓐ. 10

ⓑ. 15

ⓒ. 20

ⓓ. 9

Correct Answer: 10

Explanation: The code calculates the sum of the array elements, resulting in `1 + 2 + 3 + 4 = 10`.

76. What will be the contents of the array `arr` after the following code executes?


#include <stdio.h>
int arr[6] = {1, 2, 3, 4, 5, 6};
int x = 3;
int pos;
for (pos = 0; pos < 6; pos++) {
    if (arr[pos] == x) break;
}
for (int i = pos; i < 5; i++) {
    arr[i] = arr[i + 1];
}

ⓐ. {1, 2, 4, 5, 6, 6}

ⓑ. {1, 2, 4, 5, 6}

ⓓ. {1, 2, 4, 5, 6, 0}

Correct Answer: {1, 2, 4, 5, 6, 6}

Explanation: The code finds the first occurrence of `x` and shifts elements to the left, but duplicates the last element.

77. Which of the following correctly reverses the elements of an array `arr` of size `n`?

ⓐ.


#include <stdio.h>
for (int i = 0; i < n / 2; i++) {
    int temp = arr[i];
    arr[i] = arr[n - i - 1];
    arr[n - i - 1] = temp;
}

ⓑ.


#include <stdio.h>
for (int i = 0; i < n; i++) {
    int temp = arr[i];
    arr[i] = arr[n - i - 1];
    arr[n - i - 1] = temp;
}

ⓒ.


#include <stdio.h>
for (int i = 0; i < n / 2; i++) {
    int temp = arr[i];
    arr[i] = arr[n - i];
    arr[n - i] = temp;
}

ⓓ.


#include <stdio.h>
for (int i = 0; i < n / 2; i++) {
    int temp = arr[i];
    arr[i] = arr[n - i - 2];
    arr[n - i - 2] = temp;
}

Correct Answer:


#include <stdio.h>
for (int i = 0; i < n / 2; i++) {
    int temp = arr[i];
    arr[i] = arr[n - i - 1];
    arr[n - i - 1] = temp;
}

Explanation: This code correctly swaps the elements from the beginning with the elements from the end up to the middle of the array.

78. What is the primary purpose of array insertion?

ⓐ. Adding elements at the beginning of the array

ⓑ. Adding elements at the end of the array

ⓓ. All of the above

Correct Answer: All of the above

Explanation: Array insertion can involve adding elements at the beginning, end, or any specific position in the array.

79. What will be the output of the following code?


#include <stdio.h>
int arr[5] = {1, 2, 3, 4, 5};
for (int i = 0; i < 5; i++) {
    if (arr[i] == 3) continue;
    printf("%d ", arr[i]);
}

ⓐ. 1 2 4 5

ⓑ. 1 2 3 4 5

ⓒ. 1 2 3 4

ⓓ. 2 3 4 5

Correct Answer: 1 2 4 5

Explanation: The `continue` statement skips the printing of the element `3`.

80. What is the correct way to initialize all elements of an array `arr` of size 10 to zero?

ⓐ.


#include <stdio.h>
int arr[10] = {0};

ⓑ.


#include <stdio.h>
int arr[10] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0};

ⓓ. Neither A nor B

Correct Answer: Both A and B

Explanation: Both methods correctly initialize all elements of the array to zero.

81. Which of the following correctly shifts all elements of an array `arr` of size `n` one position to the left?

ⓐ.


#include <stdio.h>
for (int i = 0; i < n - 1; i++) {
    arr[i] = arr[i + 1];
}

ⓑ.


#include <stdio.h>
for (int i = 0; i < n; i++) {
    arr[i] = arr[i + 1];
}

ⓒ.


#include <stdio.h>
for (int i = 1; i < n; i++) {
    arr[i] = arr[i - 1];
}

ⓓ.


#include <stdio.h>
for (int i = n - 1; i > 0; i--) {
    arr[i] = arr[i - 1];
}

Correct Answer:


#include <stdio.h>
for (int i = 0; i < n - 1; i++) {
    arr[i] = arr[i + 1];
}

Explanation: This code correctly shifts all elements one position to the left.

82. How do you pass an array to a function in C?

ⓐ. By passing the array directly

ⓑ. By passing a pointer to the array

ⓓ. By passing each element of the array

Correct Answer: By passing a pointer to the array

Explanation: In C, you pass an array to a function by passing a pointer to its first element.

83. Which of the following is a correct way to define a function that takes an integer array as an argument?

ⓐ.


#include <stdio.h>
void func(int arr[]);

ⓑ.


#include <stdio.h>
void func(int arr[10]);

ⓒ.


#include <stdio.h>
void func(int *arr);

ⓓ. All of the above

Correct Answer: All of the above

Explanation: All these declarations are valid as they all indicate that the function takes a pointer to an integer.

84. What is the correct way to call a function `printArray` that takes an integer array `arr` and its size `n`?

ⓐ.


#include <stdio.h>
printArray(arr, n);

ⓑ.


#include <stdio.h>
printArray(arr);

ⓒ.


#include <stdio.h>
printArray(&arr, n);

ⓓ.


#include <stdio.h>
printArray(&arr);

Correct Answer:


#include <stdio.h>
printArray(arr, n);

Explanation: You call the function by passing the array and its size.

85. What will be the output of the following code?


#include <stdio.h>
void modifyArray(int arr[], int n) {
    for (int i = 0; i < n; i++) {
        arr[i] += 1;
    }
}
int main() {
    int arr[3] = {1, 2, 3};
    modifyArray(arr, 3);
    for (int i = 0; i < 3; i++) {
        printf("%d ", arr[i]);
    }
    return 0;
}

ⓐ. 1 2 3

ⓑ. 2 3 4

ⓒ. 0 1 2

ⓓ. 3 4 5

Correct Answer: 2 3 4

Explanation: The function `modifyArray` increments each element of the array by 1.

86. What will be the output of the following code?


#include <stdio.h>
void printArray(int arr[], int n) {
    for (int i = 0; i < n; i++) {
        printf("%d ", arr[i]);
    }
}
int main() {
    int arr[4] = {4, 3, 2, 1};
    printArray(arr, 4);
    return 0;
}

ⓐ. 4 3 2 1

ⓑ. 1 2 3 4

ⓒ. 4 2 3 1

ⓓ. 1 3 2 4

Correct Answer: 4 3 2 1

Explanation: The function `printArray` prints each element of the array as it is.

87. How do you define a function that returns the sum of elements in an integer array?

ⓐ.


#include <stdio.h>
int sumArray(int arr[], int n);

ⓑ.


#include <stdio.h>
void sumArray(int arr[], int n);

ⓒ.


#include <stdio.h>
int sumArray(int *arr, int n);

ⓓ. Both A and C

Correct Answer: Both A and C

Explanation: Both declarations are correct since they both indicate a function that returns an integer and takes an array and its size as arguments.

88. What will be the output of the following code?


#include <stdio.h>
int sumArray(int arr[], int n) {
    int sum = 0;
    for (int i = 0; i < n; i++) {
        sum += arr[i];
    }
    return sum;
}
int main() {
    int arr[4] = {1, 2, 3, 4};
    printf("%d", sumArray(arr, 4));
    return 0;
}

ⓐ. 10

ⓑ. 11

ⓒ. 9

ⓓ. 12

Correct Answer: 10

Explanation: The function `sumArray` calculates the sum of the array elements, which is `1 + 2 + 3 + 4 = 10`.

89. Which of the following is true about arrays and functions in C?

ⓐ. Arrays are passed by value to functions

ⓑ. Arrays are passed by reference to functions

ⓓ. Only the first element of an array is passed to functions

Correct Answer: Arrays are passed by reference to functions

Explanation: When an array is passed to a function, a pointer to the first element is passed, so the function can modify the original array.

90. How do you pass a two-dimensional array to a function in C?

ⓐ. By passing the array directly

ⓑ. By passing a pointer to the array

ⓓ. By passing each row of the array separately

Correct Answer: By specifying the dimensions in the function parameters

Explanation: You need to specify the second dimension when passing a two-dimensional array to a function.

91. Which of the following is a correct way to define a function that takes a two-dimensional integer array as an argument?

ⓐ.


#include <stdio.h>
void func(int arr[][]);

ⓑ.


#include <stdio.h>
void func(int arr[10][]);

ⓒ.


#include <stdio.h>
void func(int arr[][10]);

ⓓ.


#include <stdio.h>
void func(int *arr[10]);

Correct Answer:


#include <stdio.h>
void func(int arr[][10]);

Explanation: You need to specify at least the second dimension when defining a function that takes a two-dimensional array.

92. What will be the output of the following code?


#include <stdio.h>
void modifyArray(int arr[][3], int rows) {
    for (int i = 0; i < rows; i++) {
        for (int j = 0; j < 3; j++) {
            arr[i][j] += 1;
        }
    }
}
int main() {
    int arr[2][3] = {{1, 2, 3}, {4, 5, 6}};
    modifyArray(arr, 2);
    for (int i = 0; i < 2; i++) {
        for (int j = 0; j < 3; j++) {
            printf("%d ", arr[i][j]);
        }
    }
    return 0;
}

ⓐ. 1 2 3 4 5 6

ⓑ. 2 3 4 5 6 7

ⓒ. 1 3 3 5 5 7

ⓓ. 2 4 4 6 6 8

Correct Answer: 2 3 4 5 6 7

Explanation: The function `modifyArray` increments each element of the two-dimensional array by 1.

93. How do you declare a function that takes an array of pointers to integers?

ⓐ.


#include <stdio.h>
void func(int *arr[]);

ⓑ.


#include <stdio.h>
void func(int **arr);

ⓒ.


#include <stdio.h>
void func(int arr[10]);

ⓓ. Both A and B

Correct Answer: Both A and B

Explanation: Both declarations indicate that the function takes an array of pointers to integers.

94. What is the correct way to pass an array and its size to a function that modifies its elements?

ⓐ.


#include <stdio.h>
void modify(int arr[], int n);

ⓑ.


#include <stdio.h>
void modify(int *arr, int n);

ⓓ. Neither A nor B

Correct Answer: Both A and B

Explanation: Both declarations are correct since they both indicate a function that takes a pointer to an array and its size as arguments.

95. What will be the output of the following code?


#include <stdio.h>
void printEven(int arr[], int n) {
    for (int i = 0; i < n; i++) {
        if (arr[i] % 2 == 0) {
            printf("%d ", arr[i]);
        }
    }
}
int main() {
    int arr[5] = {1, 2, 3, 4, 5};
    printEven(arr, 5);
    return 0;
}

ⓐ. 1 2 3 4 5

ⓑ. 2 4

ⓒ. 1 3 5

ⓓ. 1 2 4 5

Correct Answer: 2 4

Explanation: The function `printEven` prints only the even elements of the array.

96. Which of the following is a correct way to define a function that returns the maximum element in an integer array?

ⓐ.


#include <stdio.h>
int maxElement(int arr[], int n);

ⓑ.


#include <stdio.h>
void maxElement(int arr[], int n);

ⓒ.


#include <stdio.h>
int maxElement(int *arr, int n);

ⓓ. Both A and C

Correct Answer: Both A and C

Explanation: Both declarations are correct since they both indicate a function that returns an integer and takes an array and its size as arguments.

97. What will be the output of the following code?


#include <stdio.h>
int maxElement(int arr[], int n) {
    int max = arr[0];
    for (int i = 1; i < n; i++) {
        if (arr[i] > max) {
            max = arr[i];
        }
    }
    return max;
}
int main() {
    int arr[5] = {5, 8, 3, 9, 2};
    printf("%d", maxElement(arr, 5));
    return 0;
}

ⓐ. 5

ⓑ. 9

ⓒ. 3

ⓓ. 8

Correct Answer: 9

Explanation: The function `maxElement` finds and returns the maximum element in the array, which is 9.

98. Which of the following statements is true regarding arrays as function arguments in C?

ⓐ. An entire array cannot be returned from a function.

ⓑ. Array size must be explicitly passed as a parameter to the function.

ⓓ. Functions cannot modify elements of an array passed as an argument.

Correct Answer: Array size must be explicitly passed as a parameter to the function.

Explanation: When passing an array to a function, the size of the array must be explicitly passed as a parameter.

99. What will be the output of the following code?


#include <stdio.h>
void doubleArray(int arr[], int n) {
    for (int i = 0; i < n; i++) {
        arr[i] *= 2;
    }
}
int main() {
    int arr[4] = {1, 2, 3, 4};
    doubleArray(arr, 4);
    for (int i = 0; i < 4; i++) {
        printf("%d ", arr[i]);
    }
    return 0;
}

ⓐ. 1 2 3 4

ⓑ. 2 4 6 8

ⓒ. 1 4 9 16

ⓓ. 0 0 0 0

Correct Answer: 2 4 6 8

Explanation: The function `doubleArray` doubles each element of the array.

100. Which of the following is the correct way to define a function that takes an array of characters as an argument?

ⓐ.


#include <stdio.h>
void func(char *arr);

ⓑ.


#include <stdio.h>
void func(char arr[]);

ⓒ.


#include <stdio.h>
void func(char arr[10]);

ⓓ. All of the above

Correct Answer: All of the above

Explanation: All these declarations are valid and indicate a function that takes an array of characters as an argument.

Arrays MCQs – Part 1

Related MCQs