Data Structures Algorithms Online Quiz


Following quiz provides Multiple Choice Questions (MCQs) related to Data Structures Algorithms. You will have to read all the given answers and click over the correct answer. If you are not sure about the answer then you can check the answer using Show Answer button. You can use Next Quiz button to check new set of questions in the quiz.

Questions and Answers

Q 1 - Which of the following usees FIFO method

A - Queue

B - Stack

C - Hash Table

D - Binary Search Tree

Answer : A


Queue maintains two pointers − front and rear. In queue data structure, the item inserted first will always be removed first, hence FIFO!

Q 2 - Postfix expression is just a reverse of prefix expression.

A - True

B - False

Answer : B


Expression notations are not reverse (or so) of each other, rather operators used in the expression have different arrangements.

Q 3 - Minimum number of queues required for priority queue implementation?

A - 5

B - 4

C - 3

D - 2

Answer : D


Minimum number of queues required for priority queue implementation is two. One for storing actual data and one for storing priorities.

Q 4 - Which of the following algorithm is not stable?

A - Bubble Sort

B - Quick Sort

C - Merge Sort

D - Insertion Sort

Answer : B


Among the given, only quick sort is not stable that is it may re-arrange the already sorted items.

Answer : C


An algorithm is a step by step procedure to solve a computer problem.

Q 6 - Which of the below given sorting techniques has highest best-case runtime complexity −

A - quick sort

B - selection sort

C - insertion sort

D - bubble sort

Answer : B


Selection sort best case time complexity is Ο(n2)

Q 7 - Which of the following is not possible with an array in C programming langauge −

A - Declaration

B - Definition

C - Dynamic Allocation

D - Array of strings

Answer : C


Array in C are static and cannot be shrinked or expanded in run-time.

Q 8 - In C programming, when we remove an item from bottom of the stack, then −

A - The stack will fall down.

B - Stack will rearranged items.

C - It will convert to LIFO

D - This operation is not allowed.

Answer : B


Stack can only be accessed from top of it.

Q 9 - Access time of a binary search tree may go worse in terms of time complexity upto

A - Ο(n2)

B - Ο(n log n)

C - Ο(n)

D - Ο(1)

Answer : C


At maximum, BST may need to search all n values in the tree in order to access an element, hence, Ο(n).

Answer : C


A stable sorting algorithm like bubble sort, does not change the sequence of appearance of similar element in the sorted list.