<![CDATA[#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<math.h>
/*declaring a structure to create a node*/
struct node
{
int data;
struct node *next;
};
struct node *start;
/* inserting nodes into the list*/
/*function to insert values from beginning of the the single linked list*/ void insertbeg(void)
{
struct node *nn;
int a;
/*allocating implicit memory to the node*/
nn=(struct node *)malloc(sizeof(struct node));
printf("enter data:"); scanf("%d",&nn->data); a=nn->data; if(start==NULL) {
nn->next=NULL;
start=nn;
}
else
{
nn->next=start;
start=nn;
}
printf("%d succ. inserted\n",a);
return;
}
/*function to insert values from the end of the linked list*/
void insertend(void)
{
struct node *nn,*lp;int b;
nn=(struct node *)malloc(sizeof(struct node));
printf("enter data:");
scanf("%d",&nn->data);
b=nn->data;
if(start==NULL)
{
nn->next=NULL;
start=nn;
}
else
{
lp=start;
while(lp->next!=NULL)
{
lp=lp->next;
}
lp->next=nn;
nn->next=NULL;
}
printf("%d is succ. inserted\n",b);
return;
}
/*function to insert values from the middle of the linked list*/ void insertmid(void)
{
struct node *nn,*temp,*ptemp;int x,v;
nn=(struct node *)malloc(sizeof(struct node));
if(start==NULL)
{
printf("sll is empty\n"); return;
}
printf("enter data before which no. is to be inserted:\n");
scanf("%d",&x);
if(x==start->data)
{
insertbeg();
return;
}
ptemp=start;
temp=start->next;
while(temp!=NULL&&temp->data!=x)
{
ptemp=temp;
temp=temp->next;
}
if(temp==NULL)
{
printf("%d data does not exist\n",x);
}
else
{
printf("enter data:");
scanf("%d",&nn->data);
v=nn->data;
ptemp->next=nn;
nn->next=temp;
printf("%d succ. inserted\n",v);
}
return;
}
/*deletion operation*/
void deletion(void)
{
struct node *pt,*t;
int x;
if(start==NULL)
{
printf("sll is empty\n");
return;
}
printf("enter data to be deleted:");
scanf("%d",&x);
if(x==start->data)
{
t=start;
/* assigning first node pointer to next nod pointer to delete a data from the starting of the node*/
start=start->next;
free(t);
printf("%d is succ. deleted\n",x);
return;
}
pt=start;
t=start->next;
while(t!=NULL&&t->data!=x)
{
pt=t;t=t->next;
}
if(t==NULL)
{
printf("%d does not exist\n",x);return;
}
else
{
pt->next=t->next;
}
printf("%d is succ. deleted\n",x);
free(t);
return;
}
void display(void)
{
struct node *temp;
if(start==NULL)
{
printf("sll is empty\n");
return;
}
printf("elements are:\n");
temp=start;
while(temp!=NULL)
{
printf("%d\n",temp->data);
temp=temp->next;
}
return;
}
/* main program*/
int main()
{
int c,a; start=NULL;
do
{
printf("1:insert\n2:delete\n3:display\n4:exit\nenter choice:");
scanf("%d",&c);
switch(c)
{
case 1:
printf("1:insertbeg\n2:insert end\n3:insert mid\nenter choice:");
scanf("%d",&a);
switch(a)
{
case 1:insertbeg(); break;
case 2:insertend(); break;
case 3:insertmid(); break;
}
break;
case 2:deletion(); break;
case 3:display(); break;
case 4:printf("program ends\n");break;
default:printf("wrong choice\n");
break;
}
}while(c!=4);return 0;
}
]]>
