Queue

FIFO operations, circular queue, and Go's channel-based queues.

5 min readMastering Data Structures & Algorithms for Software Engineering InterviewsCode

Queue Concept

A queue is a FIFO (First In, First Out) data structure. Like a line of people — first person in line gets served first. Operations: enqueue (add to rear), dequeue (remove from front), peek (view front).

Implementations

Goqueue-with-slice-(o(n)-dequeue)-vs-linked-list-(o(1)).go

30 linesLn 1, Col 1Go

Slice queue: enqueue O(1) amortized, dequeue O(n). Linked list: both O(1) but more memory overhead. Go's slice is often fine for small queues.

Circular Queue

Fixed-size array with head/tail indices that wrap around. Avoids shifting. Used when max size is known and fixed.

Gocircular-queue-(ring-buffer).go

26 linesLn 1, Col 1Go

Modulo arithmetic wraps indices. Size tracks actual elements (distinguishes full from empty). O(1) all operations.

Go Channels as Queues

Go's channels are thread-safe queues. Buffered channels act as bounded queues. Unblocked on send/receive for concurrency patterns.

Gochannel-as-queue.go

27 linesLn 1, Col 1Go

Channels provide synchronized queue with blocking semantics. Buffered channel = fixed capacity. Close to signal no more sends. Range over channel drains until closed.

Mark this lesson complete to store local progress and unlock a cleaner resume path the next time you visit.