DSA: Essential Queue Interview Questions and Challenges.

1. Queue Basics

Implement a Queue Using Arrays
Implement a Queue Using Linked Lists
Implement a Circular Queue
Implement a Double-Ended Queue (Deque)
Implement a Queue Using Two Stacks
Implement a Stack Using Two Queues
Implementing a Queue Using Recursion
Circular Tour Problem (Petrol Pump Problem)
Generate Binary Numbers from 1 to N Using a Queue
Reverse the First K Elements of a Queue

2. Advanced Queue Implementations

Implement a Priority Queue
Implement a Min Priority Queue
Implement a Max Priority Queue
Implement a Queue with Dynamic Resizing
Design a Queue with Increment Operation
Implement a Queue Using a Doubly Linked List
Implement a Monotonic Queue
LRU Cache Implementation Using Queue
Implement a Queue to Support Middle Element Access
Implement Queue Sorting Using Recursion

3. Queue Problem Solving

First Non-Repeating Character in a Stream
Sliding Window Maximum
Sliding Window Minimum
Rotten Oranges (Time to Rot All Oranges)
Interleave the First Half of the Queue with the Second Half
Implement a Circular Buffer
Implement a Custom Queue with Customized Push/Pop Rules
Check if a Given Sequence of Operations is Valid for a Queue
Finding the Maximum in Every Window of Size K
Design a Queue That Supports GetMin and GetMax in O(1) Time

5. Queue and Recursion

Reverse a Queue Using Recursion
Sort a Queue Using Recursion
Interleave Two Queues Recursively
Merge Two Sorted Queues Using Recursion
Recursively Insert an Element at the Rear of a Queue
Implement a Recursive BFS for Tree Traversal
Recursively Reverse First K Elements in a Queue
Flattening a Queue of Queues
Recursive Sliding Window Maximum Using Queue
Implement Recursive Depth Calculation Using Queue

6. Queue Variants and Real-World Applications

Implement a Circular Queue Using Array and Linked List
Simulate a Printer Queue
Design a Queue for Task Scheduling (like CPU task scheduling)
Queue Implementation for Real-Time Messaging Systems
Implement a Ticketing System Using a Queue
Simulate a Banking Queue System
Design an Order Processing System Using Queues

7. Queue-Based Algorithms

Snake and Ladder Problem Using BFS
Shortest Path in a Binary Maze Using BFS
Design an Algorithm for Job Scheduling Using a Priority Queue
Zombie Matrix Problem Using BFS
Implement Level Order Traversal of a Binary Tree Using a Queue
Calculate the Time Needed to Process All Tasks Given Their Processing Time and a Queue

8. Queue Operations and Optimizations

Implement a Fixed-Size Queue Using Two Pointers
Queue with Reordering Based on Certain Conditions
Find the Median in a Stream Using Two Queues
Optimize Queue Operations for Specific Constraints
Implement Multi-Level Priority Queues

9. Queue Interview Challenges

Implement a Producer-Consumer Problem Using Queues
Check If a Queue Can Be Sorted into Another Queue Using a Stack
Design a Queue to Handle Time-Based Events (e.g., Expiring Items in a Cache)
Implement Multi-Threaded Queue Processing
Design a Queue with Real-Time Statistics Reporting

10. Queue Challenges in Competitive Programming

Sliding Window Median
Find the Minimum Time Required to Complete All Tasks Given a Queue and Cool Down Time
Print All Nodes at Distance K from a Given Node in a Binary Tree Using BFS
Merge K Sorted Queues Using a Min-Heap
Implement a Queue to Handle Multiple Data Types

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