NCERT Book Class 12 Computer Science Chapter 4 Queue PDF

Download the Class 12 Computer Science Chapter 4 Queue NCERT Book PDF free, straight from the official NCERT textbook and matched to the 2026-27 CBSE syllabus. This is the original chapter, with the exact text on the FIFO principle, FRONT and REAR ends, the enqueue, dequeue and peek operations, queue implementation in Python using a list, and the deque (double-ended queue) that the board exam is set from.

• The full NCERT chapter on the queue data structure, with all worked Python code and the back-exercise.
• Covers FIFO, enqueue and dequeue, overflow and underflow, peek, queue versus stack, and the deque.
• Pairs with the NCERT Solutions, Notes and Handwritten Notes linked lower on this page.

This is the official NCERT Computer Science Chapter 4 text, hosted free for Class 12 students and matched to the 2026-27 CBSE syllabus.

What Is Inside the Queue NCERT Book Chapter

Queue is the fourth chapter of the Class 12 Computer Science NCERT textbook. It comes right after Stack and teaches a second linear data structure, this time built on the First In First Out (FIFO) rule. The chapter mixes plain explanation with short Python code blocks, so students learn each operation by reading a small example first. The list below shows what the original chapter holds, so students know what they are downloading.

• The FIFO principle: the first element added is the first removed, the same way people are served in a bank queue.
• FRONT and REAR ends: items are added at the REAR (tail) and removed from the FRONT (head), unlike a stack which uses one end.
• Queue operations: how enqueue, dequeue and peek work, plus the overflow and underflow conditions.
• The deque: a double-ended queue where you can add or remove from both ends, with its own Python implementation.

Reading the original chapter matters because the board marks answers and code against the NCERT style. A student who has read the textbook once will trace a queue and write enqueue and dequeue code the way the examiner expects, which the Notes and Solutions then reinforce.

Topic List of the NCERT Chapter

The chapter follows a clear order, and the PDF keeps the NCERT section headings. The table below lists each section with a one-line note, so students can see the shape of the chapter before they read. It also helps with planning revision around the queue and the deque.

The most exam-heavy sections are the queue operations and the Python implementation, so students should read those slowly. The deque comes up in the back-exercise and in 3-mark and 5-mark questions, so it is worth a careful first read rather than a skim.

Queue Operations Table from the NCERT Chapter

The single most useful part of the chapter is the set of queue operations, which the board asks about almost every year. Students who know each operation and its overflow or underflow rule can answer most one-mark and two-mark queue questions on sight. A short version is below so students can see what the PDF carries, but the full worked traces are in the download.

Here is the enqueue and dequeue code exactly in the NCERT style, using a Python list, so students get used to the real form. Notice that append() adds at the rear and pop(0) removes from the front:

queue = []

# enqueue: add at the REAR
def enqueue(item):
    queue.append(item)

# dequeue: remove from the FRONT
def dequeue():
    if queue == []:
        print("Queue is empty (underflow)")
    else:
        return queue.pop(0)

The peek operation reads the front element but leaves the queue unchanged, which is a common one-mark question. The example below matches the textbook idea:

def peek():
    if queue == []:
        print("Queue is empty")
    else:
        return queue[0]

How to Download the Class 12 Computer Science Chapter 4 PDF

The PDF is free and easy to save on any device. The steps below show students how to get the Queue chapter and keep it for offline reading. No login or payment is needed at any stage.

• Open the download card at the top of this page and tap the PDF button.
• Save to your device so you can read the chapter offline, even without internet.
• Print if you prefer paper: the operation traces and the code blocks stay clear when printed.
• Pair it with the NCERT Solutions linked below to attempt the back-exercise questions as you read.

Many students search for the class 12 computer science chapter 4 queue pdf the night before a coding test, so a saved copy means you can revise even when the network is down. Keep the textbook PDF and the solved answers together for a full self-study set on the queue and the deque.

Why Read the Original NCERT Chapter

Notes and solutions are useful, but the original chapter is the source they all come from. There are clear reasons to read it at least once. The points below explain why the textbook still matters even when quick notes are everywhere.

• Board style: the chapter's own queue and deque code is the safest pattern to copy in the exam.
• Full context: the chapter explains why a queue uses two ends while a stack uses one, which notes often cut for space.
• Worked examples: the in-text traces for enqueue, dequeue and peek are exactly what board programs are built from.
• Exercise: the back-exercise is the exact set the Solutions answer, so reading it first sharpens recall.

The honest takeaway is that the textbook is the master copy. Read it once to understand each operation, then move to the Notes for revision and the Solutions for practice. That order builds stronger queue and deque code than starting from notes alone.

How the Book PDF Pairs with the Solutions and Notes

The Book PDF gives you the original text and code. To study the Queue chapter fully, use it with the other resources for the same chapter, all linked in the table below.

Tip: read the NCERT chapter first for the full picture, then revise from the Notes and test yourself with the Solutions. The textbook is where every good queue answer starts.

All NCERT Book PDFs for Class 12 Computer Science

The table links the NCERT Book PDF for every chapter in Class 12 Computer Science, so students can download the whole course in one place. Queue is highlighted.

FAQs on Queue NCERT Book PDF