Program45.c

#include <stdio.h>
#include <stdlib.h>

struct DLL
{
    int data;
    struct DLL *next;
    struct DLL *prev;
};

struct DLL *head = NULL;

void insertion_last()
{
    struct DLL *ptr, *temp;
    int item;
    ptr = (struct DLL *)malloc(sizeof(struct DLL));
    if (ptr == NULL)
    {
        printf("\nOVERFLOW");
    }
    else
    {
        printf("\nEnter value");
        scanf("%d", &item);
        ptr->data = item;
        if (head == NULL)
        {
            ptr->next = NULL;
            ptr->prev = NULL;
            head = ptr;
        }
        else
        {
            temp = head;
            while (temp->next != NULL)
            {
                temp = temp->next;
            }
            temp->next = ptr;
            ptr->prev = temp;
            ptr->next = NULL;
        }
    }
    printf("\nnode inserted\n");
}
// delete node given data
void delete_node(int data)
{

    struct DLL *temp = head;
    while (temp != NULL)
    {
        if (temp->data == data)
        {
            // delete node
            if (temp->prev != NULL)
            {
                temp->prev->next = temp->next;
            }
            if (temp->next != NULL)
            {
                temp->next->prev = temp->prev;
            }
            else
            {
                head = NULL;
            }
        }
    }
}

void main()
{
    int n;
    printf("Enter the number of nodes you want to insert: ");
    scanf("%d", &n);
    for (int i = 0; i < n; i++)
    {
        insertion_last();
    }
    // PRINT ELEMENTS OF NODE
    struct DLL *temp = head;
    while (temp != NULL)
    {
        printf("%d ", temp->data);
        temp = temp->next;
    }

    printf("\n");
    printf("enter data to be deleted");
    int data;
    scanf("%d", &data);
    delete_node(data);
    printf("\n");
    temp = head;
    while (temp != NULL)
    {
        printf("%d ", temp->data);
        temp = temp->next;
    }
}