Computer Knowledge

Data Structures and Algorithms

1,518 Questions

Data Structures and Algorithms form the core of computer science, focusing on arrays, linked lists, trees, and sorting mechanisms. These concepts are essential for solving complex computational problems efficiently. Test takers preparing for technical and administrative IT exams will find these questions highly relevant.

Array OperationsLinked List ApplicationsSorting AlgorithmsTree Data StructuresMultilevel IndexingAlgorithm Time Complexity

Data Structures and Algorithms Questions

Multiple choice

Why do one of the simplest sorting algorithms is called bubble sort?

  1. It encases each element in a 'bubble' before sorting them.

  2. Smaller elements 'bubble' on the top.

  3. The designer hoped more people would use his sort if it have a cute name

  4. It's a mystery. Why is anything called what it is really.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Bubble sort is named for the way smaller (or larger) elements gradually 'bubble' up to their correct position at the end of the list with each pass through the array.

Multiple choice

Which algorithm would work best to sort data as it arrives, one piece at a time perhaps from a network?

  1. Insertion sort

  2. Quick sort

  3. Merge sort

  4. Selection sort
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Insertion sort is efficient for small datasets or data that is already partially sorted. It is well-suited for online algorithms where data arrives one piece at a time, as it can insert the new element into its correct position in the already sorted prefix.

Multiple choice

When would it be good idea to use bubble sort?

  1. As a place holder, until you implement something else.

  2. Any of these

  3. In a database

  4. Anywhere you have a large database that needs sorting.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Bubble sort has a high time complexity (O(n^2)) and is generally inefficient for large datasets. It is primarily used for educational purposes or as a simple placeholder when performance is not a concern.

Multiple choice

Find out the true statements.

i. Iterator is used to obtain the element in the bi-directional direction. ii. Iterator is used to obtain the elements in the forward direction only. iii. List Iterator is used to obtain the element in the bi-directional direction. iv. List Iterator is used to obtain the element in the forward direction only.

  1. i. and iii. are true

  2. i. and iv. are true

  3. ii. and iii. are true

  4. ii. and iv. are true.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This answer is correct. Iterator interface is used to obtain elements from the collection in forward direction only. ListIterator is used to obtain elements from the collection in bi-directional direction only.

Multiple choice

Which of the following statements is/are true?

i. Linked-List is sequential accessing. ii. Linked-List is random accessing. iii. Array-List is random accessing. iv. Array-List is sequential accessing.

  1. i. and iv. both are true

  2. i. and iii. both are true

  3. ii. and iii. both are true

  4. ii. and iv. both are true
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

This answer is correct. Linked-List is sequential accessing. It means that the data which is added to Linked-List will be retained in the order they are inserted whereas Array-List is random accessing. It means that the data which is added to Array-List will not be retained in the order they are inserted.

Multiple choice

Which technique is used for direct search?

  1. Binary search

  2. Linear search

  3. Tree search

  4. Hashing

  5. _
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Hashing is used for performing almost direct constant time search in case of insertion, deletion and find operations.