CS8391 DATA STRUCTURES
CS8391 Data Structures
Anna University :: Regulations 2017
Multiple Choice Questions (MCQ)
UNIT I LINEAR DATA STRUCTURES – LIST
1. Which of these best describes an array?
a) A data structure that shows a hierarchical behaviour
b) Container of objects of similar types
c) Arrays are immutable once initialised
d) Array is not a data structure
Answer: b
2. How do you initialize an array in C?
a) int arr[3] = (1,2,3);
b) int arr(3) = {1,2,3};
c) int arr[3] = {1,2,3};
d) int arr(3) = (1,2,3);
Answer: c
3. How do you instantiate an array in Java?
a) int arr[] = new int(3);
b) int arr[];
c) int arr[] = new int[3];
d) int arr() = new int(3);
Answer: c
4. Which of the following is a correct way to declare a multidimensional array in Java?
a) int[] arr;
b) int arr[[]];
c) int[][]arr;
1 www.studymaterialz.in
CS8391 DATA STRUCTURES
d) int[[]] arr;
Answer: c
5. a) 3 and 5
b) 5 and 3
c) 2 and 4
d) 4 and 2
Answer: a
6. a) 4
b) 5
c) ArrayIndexOutOfBoundsException
d) InavlidInputException
Answer: c
7. When does the ArrayIndexOutOfBoundsException occur?
a) Compile-time
b) Run-time
c) Not an error
d) Not an exception at all
Answer: b
8. Which of the following concepts make extensive use of arrays?
a) Binary trees
b) Scheduling of processes
c) Caching
d) Spatial locality
Answer: d
9. What are the advantages of arrays?
a) Objects of mixed data types can be stored
2 www.studymaterialz.in
CS8391 DATA STRUCTURES
b) Elements in an array cannot be sorted
c) Index of first element of an array is 1
d) Easier to store elements of same data type
Answer: d
10. What are the disadvantages of arrays?
a) Data structure like queue or stack cannot be implemented
b) There are chances of wastage of memory space if elements inserted in an array are lesser than the
allocated size
c) Index value of an array can be negative
d) Elements are sequentially accessed
Answer: b
11. Assuming int is of 4bytes, what is the size of int arr[15];?
a) 15
b) 19
c) 11
d) 60
Answer: d
12. In general, the index of the first element in an array is __________
a) 0
b) -1
c) 2
d) 1
Answer: a
13. Elements in an array are accessed _____________
a) randomly
b) sequentially
c) exponentially
3 www.studymaterialz.in
CS8391 DATA STRUCTURES
d) logarithmically
Answer: a
14. Which of the following is not a disadvantage to the usage of array?
a) Fixed size
b) There are chances of wastage of memory space if elements inserted in an array are lesser than the
allocated size
c) Insertion based on position
d) Accessing elements at specified positions
Answer: d
15. What is the time complexity of inserting at the end in dynamic arrays?
a) O(1)
b) O(n)
c) O(logn)
d) Either O(1) or O(n)
Answer: d
16. What is the time complexity to count the number of elements in the linked list?
a) O(1)
b) O(n)
c) O(logn)
d) O(n2)
Answer: b
17. a) Inserting a node at the beginning of the list
b) Deleting a node at the beginning of the list
c) Inserting a node at the end of the list
d) Deleting a node at the end of the list
Answer: c
4 www.studymaterialz.in
CS8391 DATA STRUCTURES
18. What is the space complexity for deleting a linked list?
a) O(1)
b) O(n)
c) Either O(1) or O(n)
d) O(logn)
Answer: a
19. Which of these is not an application of linked list?
a) To implement file systems
b) For separate chaining in hash-tables
c) To implement non-binary trees
d) Random Access of elements
Answer: d
20. a) Find and delete a given element in the list
b) Find and return the given element in the list
c) Find and return the position of the given element in the list
d) Find and insert a new element in the list
Answer: c
21. Which of the following is false about a doubly linked list?
a) We can navigate in both the directions
b) It requires more space than a singly linked list
c) The insertion and deletion of a node take a bit longer
d) Implementing a doubly linked list is easier than singly linked list
Answer: d
22. What is the worst case time complexity of inserting a node in a doubly linked list?
a) O(nlogn)
b) O(logn)
c) O(n)
5 www.studymaterialz.in
CS8391 DATA STRUCTURES
d) O(1)
Answer: c
23. a) head-0-1-2-3-4-5-6-tail
b) head-1-2-3-4-5-6-tail
c) head-6-1-2-3-4-5-0-tail
d) head-0-1-2-3-4-5-tail
Answer: c
24. a) Return the element at the tail of the list but do not remove it
b) Return the element at the tail of the list and remove it from the list
c) Return the last but one element from the list but do not remove it
d) Return the last but one element at the tail of the list and remove it from the list
Answer: b
25. a) head-6-1-2-3-4-5-tail
b) head-6-1-2-3-4-tail
c) head-1-2-3-4-5-6-tail
d) head-1-2-3-4-5-tail
Answer: b
26. What differentiates a circular linked list from a normal linked list?
a) You cannot have the ‘next’ pointer point to null in a circular linked list
b) It is faster to traverse the circular linked list
c) You may or may not have the ‘next’ pointer point to null in a circular linked list
d) Head node is known in circular linked list
Answer: c
27. a) Print success if a particular element is not found
b) Print fail if a particular element is not found
c) Print success if a particular element is equal to 1
6 www.studymaterialz.in
CS8391 DATA STRUCTURES
d) Print fail if the list is empty
Answer: b
28. What is the time complexity of searching for an element in a circular linked list?
a) O(n)
b) O(nlogn)
c) O(1)
d) O(n2)
Answer: a
29. Which of the following application makes use of a circular linked list?
a) Undo operation in a text editor
b) Recursive function calls
c) Allocating CPU to resources
d) Implement Hash Tables
Answer: c
30. a) Return data from the end of the list
b) Returns the data and deletes the node at the end of the list
c) Returns the data from the beginning of the list
d) Returns the data and deletes the node from the beginning of the list
Answer: d
31. a) Return data from the end of the list
b) Returns the data and deletes the node at the end of the list
c) Returns the data from the beginning of the list
d) Returns the data and deletes the node from the beginning of the list
Answer: b
32. Which of the following is false about a circular linked list?
a) Every node has a successor
7 www.studymaterialz.in
CS8391 DATA STRUCTURES
b) Time complexity of inserting a new node at the head of the list is O(1)
c) Time complexity for deleting the last node is O(n)
d) We can traverse the whole circular linked list by starting from any point
Answer: b
33. Consider a small circular linked list. How to detect the presence of cycles in this list effectively?
a) Keep one node as head and traverse another temp node till the end to check if its ‘next points to head
b) Have fast and slow pointers with the fast pointer advancing two nodes at a time and slow pointer
advancing by one node at a time
c) Cannot determine, you have to pre-define if the list contains cycles
d) Circular linked list itself represents a cycle. So no new cycles cannot be generated
Answer: b
34. A linear collection of data elements where the linear node is given by means of pointer is called?
a) Linked list
b) Node list
c) Primitive list
d) Unordered list
Answer: a
35. Consider an implementation of unsorted singly linked list. Suppose it has its representation with a
head pointer only.
Given the representation, which of the following operation can be implemented in O(1) time?
i) Insertion at the front of the linked list
ii) Insertion at the end of the linked list
iii) Deletion of the front node of the linked list
Answer: b
36. In linked list each node contain minimum of two fields. One field is data field to store the data
second field is?
a) Pointer to character
b) Pointer to integer
8 www.studymaterialz.in
CS8391 DATA STRUCTURES
c) Pointer to node
d) Node
Answer: c
37. What would be the asymptotic time complexity to add a node at the end of singly linked list, if the
pointer is initially pointing to the head of the list?
a) O(1)
b) O(n)
c) θ(n)
d) θ(1)
Answer: c
38. What would be the asymptotic time complexity to insert an element at the front of the linked list
(head is known)?
a) O(1)
b) O(n)
c) O(n2)
d) O(n3)
Answer: a
39. What would be the asymptotic time complexity to find an element in the linked list?
a) O(1)
b) O(n)
c) O(n2)
d) O(n4)
Answer: b
40. What would be the asymptotic time complexity to insert an element at the second position in the
linked list?
a) O(1)
b) O(n)
c) O(n2)
9 www.studymaterialz.in
CS8391 DATA STRUCTURES
d) O(n3)
Answer: a
41. The concatenation of two list can performed in O(1) time. Which of the following variation of
linked list can be used?
a) Singly linked list
b) Doubly linked list
c) Circular doubly linked list
d) Array implementation of list
Answer: c
42. Which of the following c code is used to create new node?
a) ptr = (NODE*)malloc(sizeof(NODE));
b) ptr = (NODE*)malloc(NODE);
c) ptr = (NODE*)malloc(sizeof(NODE*));
d) ptr = (NODE)malloc(sizeof(NODE));
Answer: a
10 www.studymaterialz.in
