Program 7: Design and Develop a program to demonstrate working of singly linked list
a) Create a linked list.
b) Insertion and deletion of a node at first position and at end position.
c) Display the contents of the linked list.
#include<stdio.h>
#include<conio.h>
#include<stdlib.h>
struct node
{
int info;
struct node *link;
};
typedef struct node* NODE;
NODE getnode()
{
NODE x;
x=(NODE)malloc(sizeof(struct node));
if(x==NULL)
{
printf("out of memory\n");
exit(0);
}
return x;
}
void freenode(NODE x)
{
free(x);
}
NODE insert_front(int item, NODE first)
{
NODE temp;
temp=getnode();
temp->info=item;
temp->link=first;
return temp;
}
NODE delete_front(NODE first)
{
NODE temp;
if(first==NULL)
{
printf("Link is empty\n");
return first;
}
temp=first;
first=first->link;
printf("The deleted item is %d \n",temp->info);
free(temp);
return first;
}
NODE insert_rear(int item,NODE first)
{
NODE temp,cur;
temp=getnode();
temp->info=item;
temp->link=NULL;
if(first==NULL)
return temp;
cur=first;
while(cur->link!=NULL)
{
cur=cur->link;
}
cur->link=temp;
return first;
}
NODE delete_rear(NODE first)
{
NODE cur=first, prev=NULL;
if(cur==NULL)
{
printf("Link is empty\n");
return first;
}
while(cur->link!=NULL)
{
prev=cur;
cur=cur->link;
}
free(cur);
prev->link=NULL;
return first;
}
void display(NODE first)
{ NODE temp=first;
if(first==NULL)
{
printf("NO NODES IN THE LIST!!\n");
return first;
}
else
{
while(temp!=NULL)
{
printf("%d ",temp->info);
temp=temp->link;
}
}
}
void main()
{
NODE first=NULL;
int choice, item;
for(;;)
{
printf("\n1.INSERT FRONT\n2.INSERT REAR\n3.DELETE FRONT\n4.DELETE REAR\
n5.DISPLAY\n");
scanf("%d",&choice);
switch(choice)
{
case 1:printf("Enter the item\n");
scanf("%d",&item);
first=insert_front(item,first);
break;
case 2:printf("Enter the item\n");
scanf("%d",&item);
first=insert_rear(item,first);
break;
case 3:first=delete_front(first);
break;
case 4:first=delete_rear(first);
break;
case 5:display(first);
break;
default:exit(0);
}
}
}
Doubly linked list
#include<stdio.h>
#include<conio.h>
#include<stdlib.h>
struct node
{
int info;
struct node *llink;
struct node *rlink;
};
typedef struct node* NODE;
NODE getnode()
{
NODE x;
x=(NODE)malloc(sizeof(struct node));
if(x==NULL)
{
printf("out of memory\n");
exit(0);
}
return x;
}
void freenode(NODE x)
{
free(x);
}
NODE insert_front(int item, NODE first)
{
NODE temp;
temp=getnode();
temp->info=item;
temp->rlink=NULL;
temp->llink=NULL;
if(first==NULL)
{
first=temp;
return;
}
temp->rlink=first;
first->llink=temp;
return temp;
}
NODE delete_front(NODE first)
{
NODE temp;
if(first==NULL)
{
printf("Link is empty\n");
return first;
}
temp=first;
first=first->rlink;
printf("The deleted item is %d \n",temp->info);
free(temp);
return first;
}
NODE insert_rear(int item,NODE first)
{
NODE temp,cur;
temp=getnode();
temp->info=item;
temp->llink=temp->rlink=NULL;
if(first==NULL)
return temp;
cur=first;
while(cur->rlink!=NULL)
{
cur=cur->rlink;
}
cur->rlink=temp;
temp->llink=cur;
cur=temp;
return first;
}
NODE delete_rear(NODE first)
{
NODE cur=first, prev=NULL;
if(cur==NULL)
{
printf("Link is empty\n");
return first;
}
while(cur->rlink!=NULL)
{
prev=cur;
cur=cur->rlink;
}
printf(" deleted ele %d", cur->info);
free(cur);
prev->rlink=NULL;
return first;
}
void display(NODE first)
{ NODE temp=first;
if(first==NULL)
{
printf("NO NODES IN THE LIST!!\n");
return first;
}
else
{
while(temp!=NULL)
{
printf("%d ",temp->info);
temp=temp->rlink;
}
}
}
void main()
{
NODE first=NULL;
int choice, item;
for(;;)
{
printf("\n1.INSERT FRONT\n2.INSERT REAR\n3.DELETE FRONT\n4.DELETE
REAR\n5.DISPLAY\n");
scanf("%d",&choice);
switch(choice)
{
case 1:printf("Enter the item\n");
scanf("%d",&item);
first=insert_front(item,first);
break;
case 2:printf("Enter the item\n");
scanf("%d",&item);
first=insert_rear(item,first);
break;
case 3:first=delete_front(first);
break;
case 4:first=delete_rear(first);
break;
case 5:display(first);
break;
default:exit(0);
}
}
}
Circular Linked List
#include<stdio.h>
#include<conio.h>
#include<stdlib.h>
struct node
{
int info;
struct node *link;
};
typedef struct node* NODE;
NODE getnode()
{
NODE x;
x=(NODE)malloc(sizeof(struct node));
if(x==NULL)
{
printf("out of memory\n");
exit(0);
}
return x;
}
void freenode(NODE x)
{
free(x);
}
NODE insert_front(int item, NODE last)
{
NODE temp;
temp=getnode();
if (last == NULL)
{
temp->info = item;
temp->link = temp;
last = temp;
}
else
{
temp->info = item;
temp->link = last->link;
last->link = temp;
}
}
NODE delete_front(NODE last)
{
NODE temp;
if (last == NULL)
{
printf("\nList is empty.\n");
return last;
}
else
{
temp = last->link;
last->link = temp->link;
free(temp);
return last;
}
}
NODE insert_rear(int item,NODE last)
{
NODE temp,cur;
temp=getnode();
if (last == NULL)
{
temp->info = item;
temp->link = temp;
last = temp;
return temp;
}
else
{
temp->info = item;
temp->link= last->link;
last->link = temp;
last = temp;
return last;
}
}
NODE delete_rear(NODE last)
{
NODE temp;
if (last == NULL)
printf("\nList is empty.\n");
temp = last->link;
while(temp->link != last)
temp = temp->link;
temp->link = last->link;
last = temp;
}
void display(NODE last)
{
NODE temp=last->link;
if (last == NULL)
printf("\nList is empty\n");
do {
printf("\t %d", temp->info);
temp = temp->link;
} while (temp != last->link);
}
void main()
{
NODE last=NULL;
int choice, item;
//clrscr();
for(;;)
{
printf("\n1.INSERT FRONT\n2.INSERT REAR\n3.DELETE FRONT\n4.DELETE
REAR\n5.DISPLAY\n");
scanf("%d",&choice);
switch(choice)
{
case 1:printf("Enter the item\n");
scanf("%d",&item);
last=insert_front(item,last);
break;
case 2:printf("Enter the item\n");
scanf("%d",&item);
last=insert_rear(item,last);
break;
case 3:last=delete_front(last);
break;
case 4:last=delete_rear(last);
break;
case 5:display(last);
break;
default:exit(0);
}
}
}
