The document presents an overview of queues, a linear data structure that operates on a first-in-first-out (FIFO) principle, detailing its implementation via arrays and linked lists. It describes various types of queues including simple queues, circular queues, priority queues, and double-ended queues (dequeues), along with basic operations like enqueue and dequeue. Additionally, it provides references for further reading on the subject.

1. PRESENTATION ON QUEUE
PRESENTED BY:YOGESH SUWAL
SUBESH SHRESTHA
DUDHARAJ LAMA
ROJAN PARIYAR
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2. CONTENTS
• INTRODUCTION
• TYPES
• OPERATIONS
• REFERENCE
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3. INTRODUCTION ON QUEUE
• Queue is a Linear Data Structure that works on First-in-First-Out
(FIFO) principle.
• It has two pointers, ‘Front’ that points to the beginning of the
queue and ‘Rear’ that points to the end of the queue.
• The ‘Front’ and ‘Rear’ pointers are manipulated constantly to
always point to the beginning and end of queue.
• It can be implemented using Arrays and Linked Lists (Recursive
and Non-recursive) methods both.
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4. QUEUE 4
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5. TYPES OF QUEUE
• 1.Simple or linear queue:
Linked lists are among the simplest and most common data
structures.
They can be used to implement several other common abstract
data types, including lists(the abstract data type), stacks, queues,
associative arrays, and S-expressions, though it is not uncommon
to implement the other data structures directly without using a
list as the basis of implementation.
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6. SIMPLE QUEUE 6
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7. TYPES OF QUEUE CONT.
• 2.Circular queue:
Circular queue is a linear data structure. It follows FIFO principle.
In circular queue,the last node is connected back to the first node to
make a circle. Circular linked list follow the First In First Out
principle. Elements are added at the rear end and the elements are
deleted at front end of the queue.
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8. CIRCULAR QUEUE 8
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9. TYPES OF QUEUE CONT.
• 3.Priority queue:
Priority queue is an abstract data type such as queues,stacks and
dictionaries.
While removing an element from a priority queue, the data item
with the highest priority is removed first.
In a priority queue, insertion is performed in the order of arrival
and deletion is performed based on the priority.
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10. PRIORITY QUEUE 10
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11. TYPES OF QUEUE CONT.
• 4.Dequeue:
A double-ended queue (dequeue) is an abstract data type that
generalizes a queue, for which elements can be added to or
removed from either the front (head) or back (tail).
It is also often called a head-tail linked list, though properly this
refers to a specific data structure implementation.
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12. ENQUEUE AND DEQUEUE OPERATION 12
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13. OPERATIONS OF QUEUE
• enqueue() − add (store) an item to the queue.
• dequeue() − remove (access) an item from the queue.
• Few more functions are required to make the above-mentioned
queue operation efficient. These are −
• peek() − Gets the element at the front of the queue without
removing it.
• isfull() − Checks if the queue is full.
• isempty() − Checks if the queue is empty.
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14. REFERENCE
• http://www.tutorialride.com/data-structures/priority-queue-in-
data-structure.html
• https://www.tutorialspoint.com/data_structures_algorithms/dsa_
queue.html
• http://www.ultimatitsolution.in/p/what-is-queue-explain-types-
of-queue.html
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15. THANK YOU 15
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