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Explain the operations of doubly linked lists
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Basic Operations

Following are the basic operations supported by a list.

• Insertion − Adds an element at the beginning of the list.
• Deletion − Deletes an element at the beginning of the list.
• Insert Last − Adds an element at the end of the list.
• Delete Last − Deletes an element from the end of the list.
• Insert After − Adds an element after an item on the list.
• Delete − Deletes an element from the list using the key.
• Display forward − Displays the complete list in a forward manner.
• Display backward − Displays the complete list in a backward manner.

## Insertion Operation

The following code demonstrates the insertion operation at the beginning of a doubly linked list.

Example

//insert link at the first location
void insertFirst(int key, int data) {

struct node *link = (struct node*) malloc(sizeof(struct node));

if(isEmpty()) {
} else {
}

//point it to old first link

//point first to new first link
}


## Deletion Operation

The following code demonstrates the deletion operation at the beginning of a doubly linked list.

Example

//delete first item
struct node* deleteFirst() {

last = NULL;
} else {
}

}


## Insertion at the End of an Operation

The following code demonstrates the insertion operation at the last position of a doubly linked list.

Example

//insert link at the last location
void insertLast(int key, int data) {

struct node *link = (struct node*) malloc(sizeof(struct node));

if(isEmpty()) {