A hospital uses a queue to manage patient appointments. a) Illustrate how patients are inserted and removed in a linear queue. b) Explain what happens when the queue becomes full but has empty slots at the front (illustrate with an example). c) How does a circular queue solve this problem?

Show how to implement a first-in, first-out queue with a priority queue. Show how to implement a stack with a priority queue.

Implement a queue using two stacks. Analyze the time complexity of enqueue and dequeue operations.