All Notes on BCA

#include<stdio.h>
#include<conio.h>
#include<malloc.h>
int pos,i,n,item;
struct doubly
{
 int data;
 struct doubly *pre, *next;
 }; struct doubly *head, *tail, *temp, *temp1, *temp2, *nw;


void insert_b()
{
int item;
clrscr();
  printf("Enter Item : ");
  scanf("%d",&item);
   nw = (struct doubly *)malloc(sizeof(struct doubly));
   nw -> data = item;
   nw -> pre = NULL;
   nw -> next = head;
   head ->pre = nw;
   head = nw;
 }


void insert_e()
{
int item;
clrscr();
  printf("Enter Item : ");
  scanf("%d",&item);
   while(temp->next != NULL)
    {
     temp = temp -> next;
     }

   nw = (struct doubly *)malloc(sizeof(struct doubly));
   nw -> data = item;
    temp -> next = nw;
    nw ->pre = temp;
   temp = nw;
   nw ->next = NULL;
 }

void insert_m()
{
temp1=head;
temp2=head;
 clrscr();
  printf("Enter Your Position : ");
  scanf("%d",&pos);
    printf("Enter Item : ");
    scanf("%d",&item);
   for(i=1;i next;
     }
     temp2=temp1 -> next;

     nw = (struct doubly *)malloc(sizeof(struct doubly));
     nw    -> data = item;
     temp1 -> next = nw;
     nw    -> next = temp2;
     temp2 -> pre = nw;
     nw    -> pre = temp1;
  }

void delete_b()
{
 clrscr();
 temp = head;
 head = head ->next;
  printf("%d is deleted.",temp->data);
  free(temp);
 head -> pre  = NULL;
 getch();
 }

void delete_e()
{
 clrscr();
 temp = head;
  while(temp->next->next != NULL)
   {
    temp =temp->next;
    }
    printf("%d is deleted.",temp->next->data);
    free(temp->next);
     tail = temp;
     temp -> next = NULL;
     getch();

 }

void delete_m()
{
clrscr();
 temp1 = head;
 temp2 = head;
 printf("Enter Positon : ");
 scanf("%d",&pos);
   for(i=1;inext;
     }
     temp2 = temp1 -> next;
     temp1->next = temp2->next;
     printf("%d position %d is deleted.",pos,temp2->data);
      free(temp2);
     temp1->next->pre = temp1 ->next;
    getch();
 }


void display()
{
 temp= head;
  while(temp->next!= NULL)
  {
   printf("\n\t%d",temp->data);
   temp= temp->next;
  }
  printf("\n\t%d",temp->data);
 }

void main()
{
int item,ch;
do
{
clrscr();
 printf("1. Insert Node of Beginning : \n2. Insert Node of middle any Posistion\n3. Insert Node of Ending : \n4. Delete Node of Beginning\n5. Delete Node of middle any position\n6. Delete Node of Ending\n7. Display\n8. Exit\n\n ");
 printf("Enter Your Choice : ");
 scanf("%d",&ch);
  switch(ch)
   {
    case 1:
      insert_b();
     break;
    case 2:
      insert_m();
     break;
    case 3:
      insert_e();
     break;
    case 4:
      delete_b();
     break;
    case 5:
      delete_m();
     break;
    case 6:
      delete_e();
     break;
    case 7:
      clrscr();
      display();
      getch();
     break;
    case 8:
      printf("Thank U");
     break;

     }
   }while(ch != 8);
 }