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Queue Data Structure Questions

DSA

10 questions

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Question 1

Which of the following algorithms does NOT inherently rely on a queue data structure?

Breadth-first search
Dijkstra's shortest path algorithm
Level order traversal of a binary tree
Depth-first search

Question 2

You are designing a text editor with an undo/redo functionality. You want to store the history of operations efficiently, allowing the user to undo and redo actions in any order. Which data structure, built using deques, is best suited for this scenario?

A deque is not suitable for this scenario
Two separate deques, one for undo and one for redo
A single deque where undo operations are stored at the front and redo operations at the back
A deque of deques, where each inner deque represents a state of the text editor

Question 3

What is a significant disadvantage of implementing a queue using a single linked list compared to a doubly linked list?

Slower enqueue operations as the tail needs to be traversed
More complex implementation logic
Inability to perform efficient dequeue operations
Increased memory usage due to the extra 'next' pointer

Question 4

What is a potential drawback of implementing a queue using a fixed-size array?

The inability to handle a queue size exceeding the array's capacity
Increased time complexity for enqueue and dequeue operations
Higher memory usage compared to a linked list implementation
Difficulty in searching for specific elements within the queue

Question 5

What is the time complexity of enqueue and dequeue operations in a well-implemented queue using a linked list?

O(log n)
O(n)
O(n log n)
O(1)

Question 6

Which queue implementation is generally preferred when you need to prioritize elements based on certain criteria, leading to elements being dequeued out of their standard FIFO order?

Array-based queue
Linked list-based queue
Circular queue
None of the above

Question 7

In the context of operating systems, which of the following is a common use case for a queue?

Managing the order of function calls in a program
Storing frequently accessed data for faster retrieval
Scheduling processes for execution by the CPU
Maintaining the order of packets in a network router

Question 8

You are building a system to manage a print queue for a network printer. Multiple computers can send print jobs (represented as objects) to the queue. Which feature of a deque would be MOST beneficial for allowing users to prioritize urgent print jobs?

The ability to insert elements at the front (push_front())
Constant time complexity for accessing the last element (back())
Random access to elements in the deque
The ability to iterate through the deque in reverse order

Question 9

In what scenario would using a deque NOT provide a significant performance advantage over a regular queue?

When implementing a Least Recently Used (LRU) cache with a fixed size
When implementing a job scheduling queue with different priority levels
When processing a stream of data in a First-In, First-Out (FIFO) manner
When elements need to be added and removed from both ends frequently

Question 10

Imagine you need to implement a system that keeps track of the last N requests made to a server, along with their timestamps. This data is used for monitoring and analyzing recent server activity. Which deque operation would be MOST frequently used for maintaining this sliding window of requests?

front()
pop_front()
push_back()
push_front()