CMSACOR05P: Data Structures Lab
9. Create and perform different operations on Double-ended Queues using Linked List implementation.
PROGRAME CODE
#include<stdio.h>
#include<iostream>
using namespace std;
class node{
public:
int key;
int data;
node* link1;
node(){
key=0;
data=0;
link1=NULL;
}
};
class de_queue{
public:
node* head;
de_queue(){
head=NULL;
}
int check(int n){
node* ptr=head;
while(ptr!=NULL){
if(ptr->key==n)
return 1;
ptr=ptr->link1;
}
return 0;
}
void queue(node* n){
if(head==NULL)
head=n;
else{
if(check(n->key))
cout<<"THIS
KEY IS ALREADY EXIST...TRY WITH ANOTHER KEY .."<<endl;
else{
node* ptr=head;
while(ptr!=NULL){
if(ptr->link1==NULL){
ptr->link1=n;
break;
}
ptr=ptr->link1;
}
}
}
}
void stenqueue(node* n){
if(head==NULL)
head=n;
else{
if(check(n->key))
cout<<"THIS
KEY IS ALREADY EXIST...TRY WITH ANOTHER KEY .."<<endl;
else{
n->link1=head;
head=n;
cout<<"INSERT
A DATA SUCCESSFULLY FROM FRONT...."<<endl;
}
}
}
void lastenqueu(node* n){
if(head==NULL)
head=n;
else{
if(check(n->key))
cout<<"THIS
KEY IS ALREADY EXIST...TRY WITH ANOTHER KEY .."<<endl;
else{
node* ptr=head;
while(ptr!=NULL){
if(ptr->link1==NULL){
ptr->link1=n;
break;
}
ptr=ptr->link1;
}
cout<<"INSERT
DATA SUCCESSFULLY FROM REAR ...."<<endl;
}
}
}
void stdqueue(){
if(head==NULL)
cout<<"THE QUEUE IS
EMPTY ...."<<endl;
else{
head=head->link1;
cout<<"DELETE AN
ELEMENT SUCCESSFULLY FROM FRONT ...."<<endl;
}
}
void lastdqueue(){
if(head==NULL)
cout<<"THE QUEUE IS
EMPTY........."<<endl;
else{
node* ptr=head;
node* ptr1=NULL;
while(ptr->link1!=NULL){
ptr1=ptr;
ptr=ptr->link1;
}
ptr1->link1=NULL;
cout<<"DELETE AN
ELEMENT SUCCESSFULLY FROM REAR..."<<endl;
}
}
void display(){
if(head==NULL)
cout<<"THE QUEUE IS
EMPTY ...."<<endl;
else{
node* ptr=head;
while(ptr!=NULL){
cout<<"("<<ptr->key<<","<<ptr->data<<")->";
ptr=ptr->link1;
}
}
}
};
int main(){
de_queue ob;
int opt=0;
do{
cout<<"\nPRESS 0 TO EXIT
...."<<endl;
cout<<"PRESS 1 TO INSERT DAAT IN QUEUE
....."<<endl;
cout<<"PRESS 2 TO ENQUEUE AT FIRST
...."<<endl;
cout<<"PRESS 3 TO ENQUEUE AT
LAST......"<<endl;
cout<<"PRESS 4 TO DEQUEUE AT
FIRST......"<<endl;
cout<<"PRESS
5 TO DEQUEUE AT LAST......"<<endl;
cout<<"PRESS 6 TO
DISPLAY......"<<endl;
cin>>opt;
node *n=new node();
switch(opt){
case 0:
break;
case 1:
cout<<"ENTER THE KEY
OF THE DATA ->"<<endl;
cin>>n->key;
cout<<"ENTER THE
DATA ->"<<endl;
cin>>n->data;
ob.queue(n);
break;
case 2:
cout<<"ENTER THE KEY
OF THE DATA ->"<<endl;
cin>>n->key;
cout<<"ENTER THE
DATA ->"<<endl;
cin>>n->data;
ob.stenqueue(n);
break;
case 3:
cout<<"ENTER THE KEY
OF THE DATA ->"<<endl;
cin>>n->key;
cout<<"ENTER THE
DATA ->"<<endl;
cin>>n->data;
ob.lastenqueu(n);
break;
case 4:
ob.stdqueue();
break;
case 5:
ob.lastdqueue();
break;
case 6:
ob.display();
break;
default:
cout<<"...............ERROR..............."<<endl;
break;
}
}while(opt!=0);
return 0;
}
