Program
: Doubly Linked List – Deletion
// Deletion in doubly linked list(Delete First, Last and
node at desire position)
#include<stdio.h>
#include<conio.h>
#include<stdlib.h>
struct link
{
int
no;
struct
link *next;
struct
link *pre;
};
struct link *node,*start,*new1;
void create_link(struct link
*node);
void display(struct link *node);
void delete_first(struct link
*node);
void delete_last(struct link
*node);
void delete_desireposition(struct
link *node);
void main()
{
int
ch;
clrscr();
do
{
printf("\n
Doubly Linked List");
printf("\n---------------------------");
printf("\n
1. Create Link");
printf("\n
2. Traverse Link");
printf("\n
3. Delete First node");
printf("\n
4. Delete Last node ");
printf("\n
5. Delete node at Desire Position ");
printf("\n
6. Exit");
printf("\n-----------------------------");
printf("\n
Enter your choice:-");
scanf("%d",&ch);
switch(ch)
{
case
1:
node=(struct
link *)malloc(sizeof(struct link));
create_link(node);
printf("\n Linked list
is as follow");
display(node);
break;
case
2:
printf("\n
Output\n");
display(node);
break;
case
3:
delete_first(node);
printf("\n
After Deleting First Node");
display(node);
break;
case
4:
delete_last(node);
printf("\n
After Deleting Last Node");
display(node);
break;
case
5:
delete_desireposition(node);
printf("\n
After Deleting At Desire Position");
display(node);
break;
case
6:
exit(0);
break;
default:
printf("\n
Wrong Choice");
}
}while(ch!=6);
getch();
}
void create_link(struct link
*node)
{
char
ans;
start->next=NULL;
start->pre=NULL;
node=start;
fflush(stdin);
printf("\n
Enter 'n' for break:-");
ans=getchar();
while(ans!='n')
{
node->next=(struct
link *)malloc(sizeof(struct link));
node->next->pre=node;
node=node->next;
printf("\n
Enter data for node:-");
scanf("%d",&node->no);
node->next=NULL;
fflush(stdin);
printf("\n
Enter 'n' for break:-");
ans=getchar();
}
}
void display(struct link *node)
{
node=start->next;
while(node)
{
printf("\n %d",node->no);
node=node->next;
}
}
void delete_first(struct link
*node)
{
node=start->next;
node->pre->next=node->next;
node->next->pre=node->pre;
free(node);
}
void delete_last(struct link
*node)
{
int
node_no=0;
node=start->next;
if(node==NULL)
{
printf("\n
List is empty");
exit(0);
}
while(node)
{
node=node->next;
node_no++;
}
node=start->next;
while(node_no!=1)
{
node=node->next;
node_no--;
}
if(node_no==1)
{
node->pre->next=node->next;
node->next->pre=node->pre;
node->next=NULL;
free(node);
}
}
void delete_desireposition(struct
link *node)
{
int
node_no=1,delete_no,flag=0;
node=start->next;
if(node==NULL)
{
printf("\n
List is emplty");
getch();
exit(0);
}
printf("\n
Enter position where you want to delete node:-");
scanf("%d",&delete_no);
while(node)
{
if(node_no==delete_no)
{
node->pre->next=node->next;
node->next->pre=node->pre;
free(node);
flag=1;
break;
}
else
{
node=node->next;
}
node_no++;
}
if(flag==0)
{
printf("\n
Position not found");
}
}
Posted By : Ruchita Pandya
