The document provides algorithms for implementing a queue using a linked list, detailing the steps for pushing and popping elements. It also describes the structure of a doubly linked list, including the fields for each node and how it differs from a singly linked list. Additionally, it highlights that operations available for singly linked lists can also be applied to doubly linked lists.

1. QUEUE USING LINKED LIST
ALGORITHM FOR PUSHING AN ELEMENT TO A QUEUE
1. Input the VALUE element to be pushed
2. Create a New Node
3. NewNode -> DATA = VALUE
4. NewNode -> Next = NULL
// if it is not empty
5. If(REAR not equal to NULL)
(a) REAR -> next = NewNode
(b) REAR = NewNode
6. Else
REAR = FRONT = NewNode
7. Exit
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2. QUEUE USING LINKED LIST
ALGORITHM FOR POPPING ELEMENT FROM A QUEUE
1. If (FRONT is equal to NULL)
Display "The Queue is
empty"
2. Else
(a) print FRONT -> DATA
(b) TEMP = FRONT
(c) FRONT = FRONT -> Next
(d) If(FRONT is equal to NULL)
REAR = NULL
(e) Free the TEMP node
3. Exit
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3. DOUBLY LINKED LIST
Every nodes in the doubly linked list has three fields:
LeftPointer, RightPointer and DATA.
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4. REPRESENTATION OF DOUBLY LINKED LIST
•A node in the doubly linked list can be represented
with the following declarations:
struct Node
{
int DATA;
Node * next;
Node * prev;
};
Node *
START;
•All operations performed on singly linked list can also
be performed on doubly linked list. 39