Hash Tables: Master Data Retrieval with Hashing Techniques

Question 1

Which practical scenario best showcases the effective use of hash tables?

Accepted Answer

Caching frequently accessed data

Answer

Storing user passwords securely

Answer

Managing file systems

Answer

Implementing priority queues

Question 2

Which of the following is NOT a collision resolution technique commonly employed in hash tables?

Accepted Answer

Binary search tree

Answer

Open addressing

Answer

Chaining

Answer

Double hashing

Question 3

What is the load factor of a hash table with 100 keys and a size of 200?

Accepted Answer

0.5

Answer

0.6

Answer

0.7

Answer

0.8

Question 4

Which of the following is not a desirable characteristic of an effective hash function?

Accepted Answer

Collision-free operation

Answer

Deterministic behavior

Answer

Uniform distribution of output

Answer

Computational efficiency

Question 5

Which of the following is the core mechanism of a hash table?

Accepted Answer

Using a mathematical function to assign data to an array

Answer

Storing data in a sequential order

Answer

Organizing data in a tree structure

Answer

Reserving a fixed memory block for data items

Question 6

What is the primary usage of hash tables?

Accepted Answer

Storing key-value pairs for efficient retrieval

Answer

Sorting vast amounts of data

Answer

Compressing files for reduced storage needs

Answer

Implementing secure encryption algorithms

Question 7

Which of the following is NOT a characteristic of hash tables?

Accepted Answer

Maintaining data elements in sorted order

Answer

Efficient data retrieval

Answer

Fast data storage

Answer

Collision resolution mechanism

Question 8

What is the primary purpose of a hash function in a hash table?

Accepted Answer

To generate a unique index for each data item

Answer

To sort data items in ascending order

Answer

To compress data items for efficient storage

Answer

To identify duplicate data items

Question 9

Which collision resolution technique utilizes a linked list to store data items with the same hash value?

Accepted Answer

Chaining

Answer

Linear probing

Answer

Quadratic probing

Answer

Double hashing

Question 10

Which of the following is a potential limitation of using hash tables for data storage?

Accepted Answer

Hash collisions

Answer

Data integrity issues

Answer

Memory leaks

Answer

Concurrency problems

Question 11

How do hash tables differ from binary search trees in terms of data retrieval?

Accepted Answer

Hash tables use hashing, while binary search trees use comparison

Answer

Hash tables only support key-value pairs, while binary search trees can store arbitrary data

Answer

Binary search trees are more efficient for large datasets than hash tables

Answer

Hash tables are implemented using arrays, while binary search trees are implemented using linked lists

Question 12

Which of the following is NOT an advantage of using hash tables?

Accepted Answer

Guaranteed constant-time performance for all operations

Answer

Improved average-case time complexity for search and retrieval operations

Answer

Efficient handling of collisions

Answer

Reduced space complexity compared to other data structures

Question 13

What is the primary purpose of a hash function in a hash table?

Accepted Answer

To map keys to unique memory locations

Answer

To sort the data in ascending or descending order

Answer

To determine the number of collisions that will occur

Answer

To prevent the hash table from becoming full

Question 14

What does the load factor of a hash table represent?

Accepted Answer

The ratio of elements to the size of the hash table

Answer

The number of collisions that have occurred

Answer

The average number of elements per hash table bucket

Answer

The maximum capacity of the hash table

Question 15

What is the purpose of resizing a hash table?

Accepted Answer

To adjust the table size for better performance

Answer

To modify the hash function to reduce collisions

Answer

To improve search efficiency by reorganizing data

Answer

To remove duplicate elements from the table

Question 16

Is it accurate to state that hash tables always operate in constant time?

Accepted Answer

No

Answer

Yes

Question 17

Which of the following collision resolution techniques involves creating a linked list of data items that collide at the same index?

Accepted Answer

Chaining, where data items are inserted into a linked list at the index determined by their hash value

Answer

Open addressing, where data items are placed in the next available slot after their calculated index

Answer

Double hashing, where a secondary hash function is used to resolve collisions

Answer

Linear probing, where data items are placed in consecutive slots starting from their calculated index

Question 18

What is the time complexity of searching for a data item in a hash table with a well-chosen hash function and efficient collision resolution?

Accepted Answer

O(1) on average, providing near-constant time search performance

Answer

O(n), where n is the number of data items, indicating linear search complexity

Answer

O(log n), representing logarithmic search complexity, similar to binary search trees

Answer

O(n^2), indicating quadratic search complexity, making it inefficient for large data sets

Question 19

Which of the following is NOT a desirable characteristic of a good hash function?

Accepted Answer

Reversibility, allowing the original input to be easily retrieved from the hash value

Answer

Deterministic, ensuring the same input always produces the same hash value

Answer

Uniform distribution, spreading data items evenly across the hash table to minimize collisions

Answer

Collision avoidance, preventing different inputs from menghasilkan the same hash value

Question 20

What is the primary advantage of using a perfect hash function?

Accepted Answer

Eliminating collisions completely, resulting in optimal search performance

Answer

Reducing the size of the hash table, requiring less memory to store the same amount of data

Answer

Improving the performance of data retrieval, making it faster to find specific items

Answer

Enhancing data security, protecting against unauthorized access to sensitive information

Question 21

The primary advantage of using a hash table is its:

Accepted Answer

Speed in retrieving data

Answer

Reduced data storage requirements

Answer

Improved data security

Answer

Increased data accuracy

Question 22

The process of determining the index of a key in a hash table is called:

Accepted Answer

Hashing

Answer

Mapping

Answer

Indexing

Answer

Searching

Question 23

Indicate the primary advantage of using hash tables:

Accepted Answer

Enhanced efficiency for data retrieval operations

Answer

Reduced memory requirements

Answer

Simplified implementation process

Answer

Guaranteed insertion of all input data

Question 24

Which data structure is most suitable for implementing the underlying structure of a hash table?

Accepted Answer

Array

Answer

Linked list

Answer

Binary tree

Answer

Queue

Question 25

In the context of hash tables, what is referred to as a collision?

Accepted Answer

When multiple keys map to the same bucket

Answer

When the hash function returns an invalid index

Answer

When the hash table is at capacity

Answer

When the desired data item is not found

Question 26

Which collision resolution technique involves creating a linked list within each bucket?

Accepted Answer

Chaining

Answer

Linear probing

Answer

Double hashing

Answer

Open addressing

Question 27

What is the main purpose of the load factor in a hash table?

Accepted Answer

To determine the average number of keys per bucket

Answer

To establish the maximum number of permitted insertions

Answer

To calculate the probability of a collision

Answer

To optimize the hash function

Question 28

Which of the following is an essential characteristic of hash tables?

Accepted Answer

Efficient key-value retrieval

Answer

Ordered data storage

Answer

Sequential data access

Answer

Minimal memory overhead

Question 29

What is the main purpose of a hash function in a hash table?

Accepted Answer

To map input keys to unique memory addresses

Answer

To sort data in ascending order

Answer

To store data in a binary search tree

Answer

To handle collisions effectively

Question 30

Which of the following is NOT a suitable application of hash tables?

Accepted Answer

Storing sorted datasets efficiently

Answer

Caching frequently accessed data

Answer

Implementing associative arrays

Answer

Detecting duplicate elements in a list

Question 31

What is the average time complexity of searching for an element in a hash table with 'n' elements?

Accepted Answer

O(1)

Answer

O(log n)

Answer

O(n)

Answer

O(n^2)

Question 32

What is the load factor of a hash table?

Accepted Answer

The ratio of occupied slots to total slots

Answer

The sum of all key-value pairs in the table

Answer

The size of the underlying data structure

Answer

The average number of collisions per insertion

Question 33

What is the primary advantage of using a hash table over a linked list?

Accepted Answer

Constant time (O(1)) lookup time

Answer

Faster insertion and deletion operations

Answer

Reduced memory overhead

Answer

Improved cache performance

Question 34

What is the key difference between a direct-address table and a hash table?

Accepted Answer

Direct-address tables use keys directly as memory addresses, while hash tables use hash functions to compute memory addresses.

Answer

Hash tables use chaining to handle collisions, while direct-address tables use open addressing.

Answer

Direct-address tables have a fixed size, while hash tables can dynamically resize.

Answer

Hash tables are more efficient for small data sets, while direct-address tables are more efficient for large data sets.

Question 35

What is the purpose of a load factor in a hash table?

Accepted Answer

To measure the utilization of the hash table and guide resizing decisions

Answer

To determine the optimal hash function for the given data distribution

Answer

To control the collision handling strategy

Answer

To improve the performance of the hash table by reducing cache misses

Question 36

Which of the following is NOT a common implementation of hash tables?

Accepted Answer

Balanced binary search tree

Answer

Separate chaining

Answer

Linear probing

Answer

Quadratic probing

Question 37

What is the primary advantage of using hash tables compared to other data structures for efficient data retrieval?

Accepted Answer

Faster average lookup time

Answer

Smaller memory usage

Answer

Easier insertion and deletion

Answer

More secure data storage

Question 38

What is the main purpose of a load factor in a hash table?

Accepted Answer

Measuring table fullness to optimize performance

Answer

Determining the probability of collisions

Answer

Estimating retrieval time

Answer

Adjusting hash function parameters

Question 39

Which of the following collision resolution techniques involves moving to the next available slot by a fixed step size?

Accepted Answer

Linear probing

Answer

Quadratic probing

Answer

Double hashing

Answer

Chaining

Question 40

Which of the following is a benefit of using hash tables?

Accepted Answer

Improved data retrieval efficiency

Answer

Reduced storage space requirements

Answer

Efficient handling of collisions

Answer

Guaranteed uniqueness of keys

Question 41

Which of the following collision resolution techniques involves creating a linked list of overflowing elements?

Accepted Answer

Chaining

Answer

Linear Probing

Answer

Quadratic Probing

Answer

Double Hashing

Question 42

Which of the following data structures is typically used to implement the overflow area in chaining-based collision resolution?

Accepted Answer

Linked List

Answer

Array

Answer

Queue

Answer

Stack

Question 43

What is the technique of distributing elements into multiple tables to balance the load factor of a hash table called?

Accepted Answer

Sharding

Answer

Partitioning

Answer

Balancing

Answer

Folding

Question 44

What is a Bloom filter primarily used for?

Accepted Answer

Fast and space-efficient set membership testing

Answer

Efficient data storage

Answer

Collision resolution in hash tables

Answer

Hashing strings

Question 45

Which of the following is a key characteristic of hash tables?

Accepted Answer

Fast data retrieval

Answer

Ordered data storage

Answer

Limited size

Answer

Storage of duplicate keys

Question 46

What is the primary goal of a hash function in a hash table?

Accepted Answer

To determine the placement of a key-value pair

Answer

To generate unique identifiers

Answer

To minimize the size of the table

Answer

To ensure the integrity of the stored data

Question 47

Which collision resolution technique involves placing colliding elements in the next available slot in the hash table?

Accepted Answer

Linear probing

Answer

Quadratic probing

Answer

Chaining

Answer

Double hashing

Question 48

Which collision resolution method is not commonly used in hash tables?

Accepted Answer

Binary search

Answer

Chaining

Answer

Linear probing

Answer

Double hashing

Question 49

In which scenario do hash tables typically provide significant advantages?

Accepted Answer

Retrieving data from databases

Answer

Sorting large lists of integers

Answer

Traversing complex graphs

Answer

Finding the shortest path in weighted graphs

Question 50

What is a potential downside to using hash tables?

Accepted Answer

Potential collisions

Answer

Complicated implementation

Answer

Limited storage capacity

Answer

Poor search performance

Question 51

Compared to linked lists, what is a significant advantage of hash tables?

Accepted Answer

Faster lookups

Answer

Ordered storage of data

Answer

Dynamic resizing

Answer

Simplicity of implementation

Question 52

In a hash table, the load factor represents:

Accepted Answer

The ratio of the number of elements to the table size

Answer

The number of collisions in the table

Answer

The average length of the linked lists in the table

Answer

The number of times the hash function is called