Lesson 036
Queues in the Real World
FIFO · Scheduling · Buffering · BFS
1:00How the FIFO queue powers print spoolers, OS scheduling, web servers, BFS pathfinding, and streaming buffers — and what goes wrong at the boundaries.
By the end, you can
- Define FIFO and explain the difference between enqueue/dequeue and push/pop.
- Trace the state of a queue after a sequence of enqueue and dequeue operations.
- Explain why a naive array-backed queue is O(n) on dequeue and how a circular array fixes it.
- Apply modulo arithmetic to compute the new rear index after an enqueue on a circular array.
- Describe how each of the five real-world systems (print, OS, web, BFS, buffer) relies on FIFO ordering.
- Trace one round of round-robin scheduling, showing which process rejoins the tail.
- Perform a BFS traversal on a small graph using a queue, listing nodes in visit order.
- Distinguish underflow from overflow and give a real-world symptom of each.
Up next in Linear Data Structures
