Circular Singly Linked List: Delete from Front
#include<stdio.h>
#include<stdlib.h>
struct node
{
int data;
struct node *link;
};
typedef struct node* NODE;
NODE getnode();
NODE insert_at_front(NODE
last,int item);
NODE delete_at_front(NODE last);
NODE display(NODE last);
NODE getnode()
{
NODE x;
x =(NODE) malloc(sizeof(struct node));
return x;
}
NODE insert_at_front(NODE last,
int item)
{
NODE temp;
temp = getnode();
temp->data = item;
if(last == NULL)
/*Case 1: List is empty*/
{
last = temp;
}
else /*Case 2: If not empty*/
{
temp->link = last->link;
}
last->link =
temp;
return last;
}
NODE delete_at_front(NODE last)
{
NODE temp;
if(last == NULL)
{
printf("\n List is empty");
return NULL;
}
if(last->link == last)
{
printf("\nThe node %d is
deleted", last->data);
free(last);
return NULL;
}
temp = last->link;
last->link = temp->link;
printf("\nThe node
%d is deleted", temp->data);
free(temp);
return last;
}
void display(NODE last)
{
NODE cur;
printf("\nContents are:\n");
if(last == NULL)
printf("\nList is empty. Nothing to
display.");
else
{
cur = last->link;
printf("==> ");
while(cur != last)
{
printf("|
%d | %d | => ", cur->data, cur->link);
cur =
cur->link;
}
printf("| %d | %d |
=> ", cur->data, cur->link);
}
}
void main()
{
int ch, item;
NODE last = NULL;
while(1)
{
printf("\n\n~~MENU~~");
printf("\n1.Insert at front");
printf("\n2.Delete from front");
printf("\n3.Display");
printf("\n4.exit");
printf("\nEnter your choice: ");
scanf("%d",&ch);
switch(ch)
{
case
1: printf("\nEnter
the value: ");
scanf("%d",
&item);
last = insert_at_front(last, item);
break;
break;
case 2: last = delete_at_front(last);
break;
case
3: display(last);
break;
case 4: exit(0);
}
}
}
Output:
~~MENU~~
1.Insert at front
2.Delete from front
3.Display
4.exit
Enter your choice: 1
Enter the value: 11
~~MENU~~
1.Insert at front
2.Delete from front
3.Display
4.exit
Enter your choice: 3
Contents are:
==> | 11 | 7214960 | =>
~~MENU~~
1.Insert at front
2.Delete from front
3.Display
4.exit
Enter your choice: 1
Enter the value: 12
~~MENU~~
1.Insert at front
2.Delete from front
3.Display
4.exit
Enter your choice: 3
Contents are:
==> | 12 | 7214960 | => |
11 | 7214856 | =>
~~MENU~~
1.Insert at front
2.Delete from front
3.Display
4.exit
Enter your choice: 2
The node 12 is deleted
~~MENU~~
1.Insert at front
2.Delete from front
3.Display
4.exit
Enter your choice: 2
The node 11 is deleted
~~MENU~~
1.Insert at front
2.Delete from front
3.Display
4.exit
Enter your choice: 2
List is empty
~~MENU~~
1.Insert at front
2.Delete from front
3.Display
4.exit
Enter your choice: 3
Enter your choice: 3
Contents are:
List is empty. Nothing to display.
~~MENU~~
1.Insert at front
2.Delete from front
3.Display
4.exit
Enter your choice: 4Also Check,
- Circular Singly Linked List
