#include<iostream.h>

#include<conio.h>

#include<process.h>

class slink

{

private:

struct node

{

int data;

node*next;

}*head;

public:

slink()

{

head=NULL;

}

void create();

void insert();

void delnode();

void display();

};

void slink::create()

{

head=new node;

cout<<"Enter the data for the node:";

cin>>head->data;

head->next=NULL;

}

void slink::insert()

{

int n;

char p;

node*list,*prev,*temp;

list=head;

cout<<"Insert node at front/middle/last? f/m/l:"<<endl;

cin>>p;

if(p=='f')

{

temp=new node;

cout<<"Enter the data for the node:";

cin>>temp->data;

temp->next=head;

head=temp;

}

if(p=='m')

{

cout<<"Enter the data for the new node before:"<<endl;

cin>>n;

while(list->data!=n)

{

prev=list;

list=list->next;

}

temp=new node;

cout<<"Enter the data for the node:";

cin>>temp->data;

prev->next=temp;

temp->next=list;

}

if(p=='l')

{

while(list->next!=NULL)

list=list->next;

temp=new node;

cout<<"Enter the data for the node:";

cin>>temp->data;

temp->next=NULL;

list->next=temp;

}

}

void slink::delnode()

{

int n,p=0;

node *list,*prev,*temp;

list=head;

cout<<"Enter the data for the node to be deleted:";

cin>>n;

if(head->data==n)

{

head=head->next;

p=1;

}

else

{

while((list->next!=NULL)&&(list->data!=n))

{

prev=list;

list=list->next;

}

if((list->next!=NULL)&&(list->data==n))

{

temp=list;

prev->next=NULL;

p=1;

}

else if(list->data==n)

{

temp=list;

prev->next=list->next;

p=1;

}

delete(temp);

}

if(p==0)

{

cout<<"Node is not present";

}

}

void slink::display()

{

node*list;

list=head;

if(list==NULL)

cout<<"List is empty";

else

{

cout<<"The list is: ";

while(list!=NULL)

{

cout<<list->data<<"<==>";

list=list->next;

}

cout<<"NULL";

}

getch();

}

void main()

{

int option;

slink s;

while(option!=5)

{

clrscr();

cout<<"1.Create()"<<endl;

cout<<"2.Insert()"<<endl;

cout<<"3.Delete()"<<endl;

cout<<"4.Display()"<<endl;

cout<<"5.Exit()"<<endl;

cout<<"Enter your option:";

cin>>option;

switch(option)

{

case 1:

s.create();

break;

case 2:

s.insert();

break;

case 3:

s.delnode();

break;

case 4:

s.display();

break;

case 5:

break;

}

}

}