Explore topic-wise MCQs in Data Structures and Algorithms.

This section includes 81 Mcqs, each offering curated multiple-choice questions to sharpen your Data Structures and Algorithms knowledge and support exam preparation. Choose a topic below to get started.

1.

Which of the following is not a technique to avoid a collision?

A. Make the hash function appear random
B. Use the chaining method
C. Use uniform hashing
D. Increasing hash table size
Answer» E.
2.

Which of the following is a widely used form of the hash tree?

A. B+ – tree
B. T tree
C. Tiger tree hash
D. Htree
Answer» D. Htree
3.

What is the formula to find the expected number of probes for an unsuccessful search in linear probing?

A. ½(1+1/(1-⅄))
B. ½(1+1/(1-⅄)2)
C. ½(1+1/(1+⅄))
D. ½(1+1/(1+⅄)(1-⅄))
Answer» B. ½(1+1/(1-⅄)2)
4.

What is the worst case search time of a hashing using separate chaining algorithm?

A. O(N log N)
B. O(N)
C. O(N2)
D. O(N3)
Answer» C. O(N2)
5.

How many probes are required on average for insertion and successful search?

A. 4 and 10
B. 2 and 6
C. 2.5 and 1.5
D. 3.5 and 1.5
Answer» D. 3.5 and 1.5
6.

Hash tree is used in data synchronisation. In the worst case the data synchronisation takes ______ time.

A. O(logn)
B. O(n2)
C. O(nlogn)
D. O(n)
Answer» E.
7.

Which of the following is identical to that of a separate chaining hash node?

A. Linked list
B. Array
C. Stack
D. Queue
Answer» B. Array
8.

What can be the value of m in the division method?

A. Any prime number
B. Any even number
C. 2p – 1
D. 2p
Answer» B. Any even number
9.

What is the value of h(k) for the key 123456? Given: p=14, s=2654435769, w=32

A. 123
B. 456
C. 70
D. 67
Answer» E.
10.

What is the hash function used in Double Hashing?

A. (h1(k) - i*h2(k))mod m
B. h1(k) + h2(k)
C. (h1(k) + i*h2(k))mod m
D. (h1(k) + h2(k))mod m
Answer» D. (h1(k) + h2(k))mod m
11.

___________ is not a theoretical problem but actually occurs in real implementations of probing.

A. Hashing
B. Clustering
C. Rehashing
D. Collision
Answer» C. Rehashing
12.

Which of the following is not a collision resolution strategy for open addressing?

A. Linear probing
B. Quadratic probing
C. Double hashing
D. Rehashing
Answer» E.
13.

Which of the following schemes does quadratic probing come under?

A. rehashing
B. extended hashing
C. separate chaining
D. open addressing
Answer» E.
14.

What is the time complexity to delete an element from the direct address table?

A. O(n)
B. O(logn)
C. O(nlogn)
D. O(1)
Answer» E.
15.

Which of the following is a disadvantage of using separate chaining using linked lists?

A. It requires many pointers
B. It requires linked lists
C. It uses array
D. It does not resolve collision
Answer» B. It requires linked lists
16.

Which hash function satisfies the condition of simple uniform hashing?

A. h(k) = lowerbound(km)
B. h(k)= upperbound(mk)
C. h(k)= lowerbound(k)
D. h(k)= upperbound(k)
Answer» B. h(k)= upperbound(mk)
17.

Who invented the MinHash technique?

A. Weiner
B. Samuel F. B. Morse
C. Friedrich Clemens Gerke
D. Andrei Broder
Answer» E.
18.

What is the value of m' if the value of m is 19?

A. 11
B. 18
C. 17
D. 15
Answer» D. 15
19.

Hashing can be used in online spelling checkers.

A. True
B. False
Answer» B. False
20.

Which of the following is the hashing function for separate chaining?

A. H(x)=(hash(x)+f(i)) mod table size
B. H(x)=hash(x)+i2 mod table size
C. H(x)=x mod table size
D. H(x)=x mod (table size * 2)
Answer» D. H(x)=x mod (table size * 2)
21.

Hash tree is generalization of ______

A. Heap
B. Hash list
C. BST
D. B – tree
Answer» C. BST
22.

How many constraints are to be met to successfully implement quadratic probing?

A. 1
B. 2
C. 3
D. 4
Answer» C. 3
23.

Which of the following is the correct function definition for quadratic probing?

A. F(i)=i2
B. F(i)=i
C. F(i)=i+1
D. F(i)=i2+1
Answer» B. F(i)=i
24.

Which of the following is true for a Hash tree?

A. Hashing is used for sequential access
B. Indexing is used for direct access
C. Hash tree allows only sequential access
D. Hashing is used for direct access
Answer» E.
25.

Which of the following is not a collision resolution technique?

A. Separate chaining
B. Linear probing
C. Quadratic probing
D. Hashing
Answer» E.
26.

In a hash table of size 10, where is element 7 placed?

A. 6
B. 7
C. 17
D. 16
Answer» C. 17
27.

Which indicator is used for similarity between two sets?

A. Rope Tree
B. Jaccard Coefficient
C. Tango Tree
D. MinHash Coefficient
Answer» C. Tango Tree
28.

What is the advantage of the multiplication method?

A. only 2 steps are involved
B. using constant
C. value of m not critical
D. simple multiplication
Answer» D. simple multiplication
29.

Sequential access in a Hash tree is faster than in B-trees.

A. True
B. False
Answer» B. False
30.

The case in which a key other than the desired one is kept at the identified location is called?

A. Hashing
B. Collision
C. Chaining
D. Open addressing
Answer» C. Chaining
31.

Which of the following operations are done in a hash table?

A. Insert only
B. Search only
C. Insert and search
D. Replace
Answer» D. Replace
32.

What should be the load factor for separate chaining hashing?

A. 0.5
B. 1
C. 1.5
D. 2
Answer» C. 1.5
33.

In linear probing, the cost of an unsuccessful search can be used to compute the average cost of a successful search.

A. True
B. False
Answer» B. False
34.

The value of h2(k) can be composite relatively to the hash table size m.

A. True
B. False
Answer» C.
35.

What is the worst case time complexity of the insertion in the hash tree?

A. O(logk(n))
B. O(n2)
C. O(nlogk(n))
D. O(kn)
Answer» B. O(n2)
36.

Where is the hash tree used?

A. in digital currency
B. in sorting of large data
C. for indexing in databases
D. in encryption of data
Answer» B. in sorting of large data
37.

Using division method, in a given hash table of size 157, the key of value 172 be placed at position ____

A. 19
B. 72
C. 15
D. 17
Answer» D. 17
38.

Double hashing is one of the best methods available for open addressing.

A. True
B. False
Answer» B. False
39.

A good hash approach is to derive the hash value that is expected to be dependent of any patterns that might exist in the data.

A. True
B. False
Answer» C.
40.

Hash tree is also known as _____

A. Merkle tree
B. T -tree
C. Hash table
D. Bx-tree
Answer» B. T -tree
41.

Which technique is used for finding similarity between two sets?

A. MinHash
B. Stack
C. Priority Queue
D. PAT Tree
Answer» B. Stack
42.

What is the hash function used in multiplication method?

A. h(k) = floor( m(kA mod 1))
B. h(k) = ceil( m(kA mod 1))
C. h(k) = floor(kA mod m)
D. h(k) = ceil( kA mod m)
Answer» B. h(k) = ceil( m(kA mod 1))
43.

How many steps are involved in creating a hash function using a multiplication method?

A. 1
B. 4
C. 3
D. 2
Answer» E.
44.

Collisions can be reduced by choosing a hash function randomly in a way that is independent of the keys that are actually to be stored.

A. True
B. False
Answer» B. False
45.

Hash tree is used in effective data verification in distributed systems.

A. True
B. False
Answer» B. False
46.

Which technique was firstly used to remove duplicate web pages from search results in AltaVista search engine?

A. MinHash
B. Stack
C. Priority Queue
D. PAT Tree
Answer» B. Stack
47.

What data organization method is used in hash tables?

A. Stack
B. Array
C. Linked list
D. Queue
Answer» D. Queue
48.

When are the members of two sets more common relatively?

A. Jaccard Index is Closer to 1
B. Jaccard Index is Closer to 0
C. Jaccard Index is Closer to -1
D. Jaccard Index is Farther to 1
Answer» B. Jaccard Index is Closer to 0
49.

Which scheme provides good performance?

A. open addressing
B. universal hashing
C. hashing by division
D. hashing by multiplication
Answer» C. hashing by division
50.

Hashing is the problem of finding an appropriate mapping of keys into addresses.

A. True
B. False
Answer» B. False