Exploring Stacks and Queues

What are the primary differences between stacks and queues?

• Stacks allow random access; Queues do not.

• Stacks can grow in any direction; Queues are always linear.

• Stacks use FIFO; Queues use LIFO.

• Stacks use LIFO; Queues use FIFO.

What is the most efficient way to implement a queue using two stacks?

• Use a single stack to handle both enqueue and dequeue operations.

• Implement a queue using three stacks for improved performance.

• Utilize two stacks where one stack is used for enqueue and the other for dequeue operations.

• Transfer elements between stacks only during dequeue operations.

In what scenarios would you prefer using a queue over a stack?

• When you need to access the most recently added item first, like in undo operations.

• When you want to process items in a last-in, first-out manner, such as in function calls.

• When the order of processing does not matter, like in random access scenarios.

• When order of processing is important, such as in task scheduling or breadth-first search.

Explain how recursion can be related to stack operations.

• Recursion eliminates the need for stack memory.

• Recursion is a method of iterative looping.

• Recursion does not involve function calls.

• Recursion uses the call stack to manage function calls and returns.

Describe a real-world application where a queue is more beneficial than a stack.

• A web browser's history where the most recent pages are accessed first.

• A customer service system where requests are handled in the order they arrive.

• A stack-based memory management system for function calls.

• A task scheduling system that prioritizes urgent tasks over arrival order.

What is the time complexity of common stack and queue operations?

• O(log n) for queue operations

• O(n) for stack operations

• O(1) for both stack and queue operations.

• O(n^2) for both stack and queue operations

How can you use a stack to check for balanced parentheses in an expression?

• Use a stack to push opening parentheses and pop for closing ones, checking for matches.

• Count the number of parentheses and ensure they are even.

• Replace all parentheses with brackets and check for balance.

• Use a queue to store parentheses and check for matches.

Discuss the implications of using a linked list versus an array for implementing a stack.

• Using a linked list provides faster access times compared to an array.

• Using a linked list allows dynamic sizing and efficient memory use, while an array offers faster access but requires fixed size.

• A linked list requires a fixed size and is less memory efficient than an array.

• An array allows for dynamic resizing and better memory management than a linked list.

What are the advantages of using a double-ended queue (deque) compared to a standard queue?

• Standard queues are more efficient for all operations.

• The advantages of using a deque include flexibility in adding/removing elements from both ends and the ability to implement more complex data structures efficiently.

• Deques only allow adding elements to the front.

• Deques can only be used for fixed-size data structures.

How can you reverse a queue using a stack?

• Use a stack to hold the elements of the queue, then transfer them back to the queue to reverse their order.

• Use two queues to swap elements back and forth.

• Sort the queue in ascending order to reverse it.

• Remove elements from the queue one by one until it's empty.