SINGLE LINK LIST
#include<stdio.h>
#include<malloc.h>
#include<stdlib.h>
typedef struct node
{
int data;
struct node *next;
}node;
int main()
{
void display(node*);
node* get_node(int );
node* creat_list(node*);
node* insert_beg(node*);
node* insert_mid(node*);
node* insert_end(node*);
node* insert_after_a_given_node(node*);
node* insert_before_a_given_node(node*);
node* del_beg(node*);
node* del_mid(node*);
node* del_end(node*);
node* del_before_an_element(node*);
node* del_after_an_element(node*);
node* del_an_element_from_a_perticular_position(node*);
node* reverse_link_list(node*);
node* head=NULL;
char ch;
int x;
do
{
printf("--------------------------------------------------\n");
printf("| SINGLE LINKED LIST |\n");
printf("--------------------------------------------------\n");
printf("| 1.Create list |\n");
printf("| 2.Display list |\n");
printf("| 3.Insert beginning |\n");
printf("| 4.Insert middle |\n");
printf("| 5.Insert end |\n");
printf("| 6.Insert after a given node |\n");
printf("| 7.Insert before a given node |\n");
printf("| 8.Delete beginning |\n");
printf("| 9.Delete middle |\n");
printf("|10.Delete end |\n");
printf("|11.Delete before an element |\n");
printf("|12.Delete after an element |\n");
printf("|13.Delete an element from a perticular position |\n");
printf("|14.Reverse link list |\n");
printf("|15.Exit from the program |\n");
printf("--------------------------------------------------\n");
printf("Enter your choice: ");
scanf("%d",&x);
printf("\n");
switch(x)
{
case 1:
head=creat_list(head);
break;
case 2:
display(head);
break;
case 3:
head=insert_beg(head);
break;
case 4:
head=insert_mid(head);
break;
case 5:
insert_end(head);
break;
case 6:
head=insert_after_a_given_node(head);
break;
case 7:
head=insert_before_a_given_node(head);
break;
case 8:
head=del_beg(head);
break;
case 9:
head=del_mid(head);
break;
case 10:
head=del_end(head);
break;
case 11:
head=del_before_an_element(head);
break;
case 12:
head=del_after_an_element(head);
break;
case 13:
head=del_an_element_from_a_perticular_position(head);
break;
case 14:
head=reverse_link_list(head);
break;
case 15:
exit(0);
default :
printf("Wrong choice\n\n");
}
}while(1);
return 1;
}
node *get_node(int x)
{
node *p;
p=(node*)malloc(sizeof (node));
p->data=x;
p->next=NULL;
return p;
}
node* creat_list(node* head)
{
node *p,*q;
int x;
head=NULL;
while(1)
{
printf("If you do not want to add data then Enter (-999)\nenter data ");
scanf("%d",&x);
if(x==-999)
break;
else
{
p=get_node(x);
if(head==NULL)
head=p;
else
q->next=p;
q=p;
}
}
return head;
}
void display(node* head)
{
node *p;
if(head==NULL)
{
printf("Link list not exist.\n");
return;
}
p=head;
while(p!=NULL)
{
printf("[%d]->",p->data);
p=p->next;
}
printf("\n\n");
}
node* insert_beg(node* head)
{
node *p;
int x;
if(head==NULL)
{
printf("Link list not exist.\n");
return head;
}
printf("Enter the value which you wand to insert at the begning ");
scanf("%d",&x);
p=get_node(x);
p->next=head;
head=p;
return head;
}
node* insert_mid(node* head)
{
node *p,*q;
int x,pos,c=1;
if(head==NULL)
{
printf("Link list not exist.\n");
return head;
}
printf("Enter the value which you wand to insert at the middle ");
scanf("%d",&x);
printf("Enter the position where you insert the given value ");
scanf("%d",&pos);
p=get_node(x);
if(pos==1)
{
p->next=head;
head=p;
return;
}
q=head;
while(c<pos-1&&q->next!=NULL)
{
c++;
q=q->next;
}
p->next=q->next;
q->next=p;
return head;
}
node* insert_end(node* head)
{
node *p,*q;
int x;
if(head==NULL)
{
printf("Link list not exist.\n");
return head;
}
printf("Enter the value which you wand to insert at the end ");
scanf("%d",&x);
p=get_node(x);
q=head;
while(q->next!=NULL)
{
q=q->next;
}
q->next=p;
return head;
}
node* insert_after_a_given_node(node* head)
{
node *p,*q;
int x,y;
if(head==NULL)
{
printf("Link list not exist.\n");
return head;
}
printf("Enter the value which you wand to insert after the node ");
scanf("%d",&x);
printf("Enter the value after you want to insert ");
scanf("%d",&y);
q=head;
p=get_node(x);
while(q->data!=y&&q->next!=NULL)
{
q=q->next;
}
if(q->data!=y)
{
printf("Entered data %d not found\n",y);
return head;
}
p->next=q->next;
q->next=p;
return head;
}
node* insert_before_a_given_node(node* head)
{
node *p,*q,*r;
int x,y;
if(head==NULL)
{
printf("Link list not exist.\n");
return head;
}
printf("Enter the value before you want to insert ");
scanf("%d",&y);
printf("Enter the value which you wand to insert before the node ");
scanf("%d",&x);
q=head;
r=head;
p=get_node(x);
if(q->data==y)
{
p->next=head;
head=p;
return head;
}
while(r->data!=y&&r->next!=NULL)
{
q=r;
r=r->next;
}
if(r->data!=y)
{
printf("Entered data not found\n");
return head;
}
p->next=q->next;
q->next=p;
return head;
}
node* del_beg(node* head)
{
node *p;
if(head==NULL)
{
printf("Link list not exist.\n");
return head;
}
p=head;
head=p->next;
free(p);
return head;
}
node* del_mid(node* head)
{
node *p,*q;
int x;
if(head==NULL)
{
printf("Link list not exist.\n");
return head;
}
p=head;
q=head;
printf("Enter the value which you wand to delete ");
scanf("%d",&x);
while(q->data!=x&&q->next!=NULL)
{
p=q;
q=q->next;
}
if(q->data!=x)
{
printf("Entered data not found\n");
return head;
}
if(p==q)
head=head->next;
else
p->next=q->next;
free(q);
return head;
}
node* del_end(node* head)
{
node *p,*q;
if(head==NULL)
{
printf("Link list not exist.\n");
return head;
}
p=head;
q=head;
while(q->next!=NULL)
{
p=q;
q=q->next;
}
if(p==q)
head=NULL;
else
p->next=NULL;
free(q);
return head;
}
node* del_before_an_element(node* head)
{
node *p,*q,*r;
int x;
if(head==NULL)
{
printf("Link list not exist.\n");
return head;
}
p=head;
q=head;
r=head;
printf("Enter the value whose previous value you wand to delete ");
scanf("%d",&x);
if(p->data==x||p->next==NULL)
{
printf("Deletion can not be done bcz there are no element before your entered number\n");
return head;
}
while(r->data!=x&&r->next!=NULL)
{
p=q;
q=r;
r=r->next;
}
if(r->data!=x)
{
printf("Entered data not found\n");
return head;
}
if(q==head)
head=r;
p->next=q->next;
free(q);
return head;
}
node* del_after_an_element(node* head)
{
node *p,*q;
int x;
if(head==NULL)
{
printf("Link list not exist.\n");
return head;
}
p=head;
q=head;
printf("Enter the value whose next value you wand to delete ");
scanf("%d",&x);
while(p->data!=x&&p->next!=NULL)
{
p=p->next;
}
if(p->next==NULL)
{
printf("deletion can not be done bcz there are no element after your entered number\n");
return head;
}
if(p->data!=x)
{
printf("Entered data not found\n");
return head;
}
q=p->next;
p->next=q->next;
free(q);
return head;
}
node* del_an_element_from_a_perticular_position(node* head)
{
node *p,*q;
int pos,c=1;
if(head==NULL)
{
printf("Link list not exist.\n");
return head;
}
printf("Enter the position which you want to delete ");
scanf("%d",&pos);
p=head;
q=head;
if(pos==1)
{
head=p->next;
free(p);
return head;
}
while(c<=pos-1&&q->next!=NULL)
{
c++;
p=q;
q=q->next;
}
p->next=q->next;
free(q);
return head;
}
node* reverse_link_list(node* head)
{
node *p,*q;
if(head==NULL)
{
printf("Link list not exist.\n");
return head;
}
p=NULL;
q=head->next;
while(head->next!=NULL)
{
head->next=p;
p=head;
head=q;
q=q->next;
}
head->next=p;
return head;
}