Arrays: A Comprehensive Guide for Beginners

Question 1

Which of the following is a disadvantage of using arrays?

Accepted Answer

Dynamic size adjustment

Answer

Efficient memory usage

Answer

Fast random access

Answer

Support for multiple data types

Question 2

Which of the following operations is NOT associated with arrays?

Accepted Answer

Searching elements

Answer

Accessing elements

Answer

Inserting elements

Answer

Updating elements

Question 3

An array of size 10 is declared to store integer values. What is the valid range of indices for this array?

Accepted Answer

0-9

Answer

1-10

Answer

0-10

Answer

-10 - 0

Question 4

What data structure is used to store a collection of elements of the same type, and allows efficient random access to its elements?

Accepted Answer

Array

Answer

Linked List

Answer

Tree

Answer

Queue

Question 5

What is the time complexity of accessing an element in an array?

Accepted Answer

O(1)

Answer

O(n)

Answer

O(log n)

Answer

O(n^2)

Question 6

Consider the following code: int[] arr = {1, 2, 3}; What is the value of arr[1]?

Accepted Answer

2

Answer

1

Answer

3

Answer

Error

Question 7

What is a multidimensional array?

Accepted Answer

An array with multiple dimensions

Answer

An array with only one dimension

Answer

An array with dynamic size

Answer

An array with elements of different data types

Question 8

Which sorting algorithm is commonly used to efficiently sort arrays?

Accepted Answer

Merge Sort

Answer

Bubble Sort

Answer

Selection Sort

Answer

Insertion Sort

Question 9

Consider the following array: int[] arr = {1, 3, 5, 7, 9}; What is the output of arr.length?

Accepted Answer

5

Answer

4

Answer

9

Answer

Error

Question 10

Which of the following operations is NOT typically performed with an array?

Accepted Answer

Sorting the data in ascending order

Answer

Accessing an element

Answer

Inserting an element

Answer

Updating an element

Question 11

Which of the following statements about arrays is **incorrect**?

Accepted Answer

Arrays can store elements of **different** data types.

Answer

Arrays are data structures that store a collection of elements of the **same** data type.

Answer

The size of an array is **fixed** at the time of its creation.

Answer

Arrays are accessed using their index, starting from **0**.

Question 12

What is the time complexity for accessing an element in an array?

Accepted Answer

O(1)

Answer

O(n)

Answer

O(log n)

Answer

O(n^2)

Question 13

Which of the following is the **correct** syntax to declare an array in Java?

Accepted Answer

int[] arr = new int[10];

Answer

int arr[10];

Answer

int[] arr;

Answer

int arr = new int[]

Question 14

What is the purpose of using a loop to iterate over an array?

Accepted Answer

To access **all** elements of the array

Answer

To search for a specific element in the array

Answer

To insert an element into the array

Answer

To delete an element from the array

Question 15

Which of the following is **not** an application of arrays in computer science?

Accepted Answer

Storing a linked list

Answer

Storing student records in a database

Answer

Representing a chessboard

Answer

Implementing a queue

Question 16

What is the key difference between a one-dimensional and a two-dimensional array?

Accepted Answer

One-dimensional arrays represent a sequence of elements, while two-dimensional arrays represent a **table** of elements.

Answer

One-dimensional arrays can only store one type of element, while two-dimensional arrays can store different types of elements.

Answer

Two-dimensional arrays can be accessed using one index, while one-dimensional arrays can be accessed using two indices.

Answer

There is **no** difference between one-dimensional and two-dimensional arrays.

Question 17

Which of the following methods can be used to sort an array in Java in **ascending** order?

Accepted Answer

sort()

Answer

sortDescending()

Answer

sort(Comparator)

Answer

sortAsc()

Question 18

Which data structure is an **alternative** to arrays that can handle dynamic resizing?

Accepted Answer

Linked lists

Answer

Binary trees

Answer

Hash tables

Answer

Stacks

Question 19

Which of the following scenarios would be best suited for the implementation of an array?

Accepted Answer

Storing a list of student names in a class roster

Answer

Tracking the number of visitors to a website over time

Answer

Managing a database of employee records

Answer

Finding the average of a set of numbers

Question 20

Which of the following is the correct syntax to declare an array of integers in Java?

Accepted Answer

int[] arr = new int[size];

Answer

int arr[size];

Answer

int[] arr = [size];

Answer

int arr = new int[size];

Question 21

What is the time complexity of accessing an element in an array?

Accepted Answer

O(1)

Answer

O(log n)

Answer

O(n)

Answer

O(n^2)

Question 22

What is the purpose of using a multidimensional array?

Accepted Answer

To store data in a multi-dimensional structure

Answer

To increase memory usage

Answer

To improve code readability

Answer

To make code more complex

Question 23

Which of the following is NOT a benefit of using arrays?

Accepted Answer

Supports dynamic memory allocation in all languages

Answer

Efficient data storage

Answer

Easy to access and modify elements

Answer

Can store different data types in some languages

Question 24

What is the difference between a jagged array and a regular array?

Accepted Answer

Jagged arrays have elements of different lengths while regular arrays have elements of the same length

Answer

Jagged arrays have elements of the same length while regular arrays have elements of different lengths

Answer

Jagged arrays are faster than regular arrays

Answer

Jagged arrays are more memory efficient than regular arrays

Question 25

What is the use of the 'length' property in an array?

Accepted Answer

To get the number of elements in the array

Answer

To set the number of elements in the array

Answer

To get the memory address of the array

Answer

To delete elements from the array

Question 26

Which of the following accurately describes the time complexity of iterating through an array using a for-each loop compared to a traditional for loop with an index?

Accepted Answer

O(n) for both for-each loop and traditional for loop

Answer

O(1) for for-each loop, O(n) for traditional for loop

Answer

O(n) for for-each loop, O(1) for traditional for loop

Question 27

Which of the following is **not** a valid array type in C programming?

Accepted Answer

Jagged Array

Answer

One-Dimensional Array

Answer

Two-Dimensional Array

Answer

Multidimensional Array

Question 28

Which syntax is correct for declaring an array of integers named 'myArray' with a size of 10 in C++?

Accepted Answer

int myArray[10];

Answer

int myArray;

Answer

int myArray[];

Answer

int* myArray;

Question 29

Rank the following array sorting algorithms in terms of their time complexity, from best to worst: Bubble Sort, Insertion Sort, Selection Sort.

Accepted Answer

Insertion Sort, Selection Sort, Bubble Sort

Answer

Bubble Sort, Insertion Sort, Selection Sort

Answer

Selection Sort, Insertion Sort, Bubble Sort

Answer

Insertion Sort, Bubble Sort, Selection Sort

Question 30

What is the purpose of the 'length' property of an array?

Accepted Answer

To determine the number of elements currently stored in the array.

Answer

To resize the array to a new size.

Answer

To sort the array in ascending order.

Answer

To search for a specific element in the array.

Question 31

What is the result of accessing an element with an index outside the valid range of an array?

Accepted Answer

An ArrayIndexOutOfBoundsException is thrown.

Answer

The program terminates with an error.

Answer

The value of the last element is returned.

Answer

The value of the first element is returned.

Question 32

Which of the following represents a two-dimensional array, also known as a matrix, with integer elements?

Accepted Answer

int[][] myArray = {{1, 2}, {3, 4}};

Answer

int myArray[2][2] = {{1, 2}, {3, 4}};

Answer

int[,] myArray = {{1, 2}, {3, 4}};

Answer

int[] myArray = {1, 2, 3};

Question 33

What is the primary purpose of a jagged array?

Accepted Answer

To represent data where rows can have different lengths.

Answer

To sort data more efficiently.

Answer

To improve memory efficiency.

Question 34

Which of the following methods is used in Java to copy the elements of an array 'original' to another array 'copy'?

Accepted Answer

System.arraycopy(original, 0, copy, 0, original.length);

Answer

array.copy()

Answer

array.clone()

Question 35

An array is a data structure that holds:

Accepted Answer

A collection of elements of the same data type

Answer

A collection of objects of different classes

Answer

A collection of objects of the same class

Answer

A collection of elements of different data types

Question 36

What is the purpose of using an index in an array?

Accepted Answer

To access a specific element in the array

Answer

To create a new array

Answer

To determine the size of the array

Question 37

Which of the following methods can be used to add an element to the end of an array?

Accepted Answer

.push()

Answer

.insert()

Answer

.add()

Question 38

What is the output of the following JavaScript code?

let arr = [1, 2, 3];
arr.pop();
console.log(arr);

Accepted Answer

[1, 2]

Answer

undefined

Answer

[1, 2, 3]

Answer

[2, 3]

Question 39

What is the time complexity of accessing an element in an array by its index?

Accepted Answer

O(1)

Answer

O(log n)

Answer

O(n)

Answer

O(n^2)

Question 40

What is the difference between a 1D array and a 2D array?

Accepted Answer

1D arrays have a single dimension while 2D arrays have two dimensions

Answer

1D arrays are faster to access than 2D arrays

Answer

1D arrays store only primitive data types while 2D arrays can store objects

Question 41

Which of the following characteristics does NOT apply to arrays?

Accepted Answer

Elements are stored in non-contiguous memory locations

Answer

Fixed in size

Answer

Contains elements of the same data type

Answer

Collection of elements referenced by an index

Question 42

Given the array 'arr = [1, 2, 3, 4, 5]', what is the value of 'arr[2]'?

Accepted Answer

3

Answer

4

Answer

1

Question 43

Consider the array 'arr = [10, 20, 30, 40, 50]'. What is the result of 'arr.length'?

Accepted Answer

5

Answer

10

Answer

50

Answer

40

Question 44

Consider the code snippet: 'int[] arr = new int[5];'. What is the initial value of each element in 'arr'?

Accepted Answer

0

Answer

The value is unspecified

Answer

1

Answer

-1

Question 45

Which of the following methods is used to sort an array of integers in ascending order?

Accepted Answer

Arrays.sort()

Answer

List.sort()

Answer

Collections.sort()

Answer

ArrayList.sort()

Question 46

What is the time complexity of searching for an element in an unsorted array of size 'n'?

Accepted Answer

O(n)

Answer

O(log n)

Answer

O(n^2)

Answer

O(1)

Question 47

Consider the following code: 'int[][] grid = new int[3][2];'. How many rows and columns does the 2D array 'grid' have?

Accepted Answer

3 rows, 2 columns

Answer

3 rows, 3 columns

Answer

2 rows, 2 columns

Answer

2 rows, 3 columns

Question 48

Which of the following is NOT an advantage of using arrays compared to linked lists?

Accepted Answer

Easier insertion and deletion of elements

Answer

None of the above

Answer

More memory efficient

Answer

Faster random access

Question 49

What is the primary purpose of using arrays in programming?

Accepted Answer

To store and organize collections of data elements of the same type.

Answer

To manage file input and output.

Answer

To create interactive user interfaces.

Answer

To perform complex mathematical operations.

Question 50

Which of the following correctly declares an array named 'numbers' to store 5 integers in Java?

Accepted Answer

int[] numbers = new int[5];

Answer

int numbers[5];

Answer

int[] numbers = {1, 2, 3, 4, 5};

Answer

int numbers(5);

Question 51

What is the index of the first element in an array?

Accepted Answer

0

Answer

It depends on the array size.

Answer

1

Answer

-1

Question 52

Given the array 'scores = {85, 92, 78, 95, 88}', how would you access the third element (value 78) in Java?

Accepted Answer

scores[2]

Answer

scores.get(2)

Answer

scores[3]

Answer

scores(3)

Question 53

Which of these operations is NOT typically performed directly on an array?

Accepted Answer

Sorting the array in descending order.

Answer

Accessing an element at a specific index.

Answer

Modifying the value of an existing element.

Answer

Finding the length of the array.

Question 54

What is a common use case for iterating through an array using a loop?

Accepted Answer

To perform an operation on each element of the array.

Answer

To declare and initialize the array.

Answer

To allocate memory for the array.

Answer

To find the maximum value in the array.

Question 55

What happens if you try to access an array element at an index that is out of bounds in Java?

Accepted Answer

An ArrayIndexOutOfBoundsException is thrown.

Answer

The program returns an unexpected value.

Answer

The array is automatically resized.

Answer

Nothing happens, the code executes normally.

Question 56

How can you determine the number of elements in an array named 'data' in Java?

Accepted Answer

data.length

Answer

data.size()

Answer

length(data)

Answer

sizeof(data)

Question 57

What is a multidimensional array?

Accepted Answer

An array of arrays, used to represent data with multiple dimensions.

Answer

An array that is sorted in ascending order.

Answer

An array with a dynamic size that can change during program execution.

Answer

An array that can store elements of different data types.

Question 58

Consider a scenario where you need to store the names of students in a class. Which data structure would be most suitable?

Accepted Answer

An array of strings.

Answer

A single integer variable.

Answer

A boolean (true/false) value.

Answer

A floating-point number.