Visualize
Queue
Enqueue at the rear, dequeue from the front — first-in-first-out.
Module · Queues
FIFO Queue Visualizer
First-In, First-Out — elements enter at the rear and exit from the front.
FRONTREAR
10
Front20
30
Rear—
—
—
Size: 3/6 · Enqueue: O(1) · Dequeue: O(1)
Queue initialized. Front is left, rear is right (FIFO).
Operation History
- #1Queue initialized. Front is left, rear is right (FIFO).
Time Complexity
Enqueue
- Average
- O(1)
- Space
- O(1)
Dequeue
- Average
- O(1)
- Space
- O(n)
Peek
- Average
- O(1)
- Space
- O(n)
How It Works
A queue follows FIFO — First-In, First-Out. Elements join at the rear and leave from the front.
Queues model task schedulers, print spoolers and Breadth First Search (BFS). Enqueue and dequeue are constant-time operations.