A study-notes page about implementing queues in C (linear array, circular array, and linked list), covering common bugs, front/rear tracking, and memory management with malloc/free.

<p><strong>Difficulty: Intermediate | Prerequisites: Queue Fundamentals study notes, comfort with C arrays, pointers, structs, and dynamic memory allocation (<code>malloc</code>, <code>free</code>).</strong></p><h2>Big Picture</h2><p>This set of notes covers the practical side of queues: writing them in C. You need to be able to implement a queue three ways (linear array, circular array, linked list), and you need to be able to spot and fix bugs in queue code. This is the kind of material that shows up as "write a function" or "find the bug" on exams. If you understand the conceptual operations from the fundamentals notes, this is where you put them into code.</p><h2>TL;DR</h2><p>There are three standard queue implementations in C: linear array, circular array, and linked list. Each uses <code>front</code> and <code>rear</code> to track the q…</p>