A double queue (deque) is a linear list in which additions and deletions can be made at both ends. Get a data representation mapping a deque to a one-dimensional array. Write a C++ program to simulate a deque with functions to add and remove elements from both ends of the deque.

A double-ended queue(deque) is a linear list in which additions and deletions may be made
at either end. Obtain a data representation mapping a deque into a one-dimensional array.
Write C++ program to simulate deque with functions to add and delete elements from either
end of the deque.

OUTPUT FOR THE PROGRAM

#include<iostream> //Header Files
using namespace std;

char que[5]; //.......Double Ended Queue
int size = 5; //.......Size of Queue
int front = -1; //.......Front End
int rear = -1; //.......Rear End

int que_full() //.......To check Queue is Full
{
   if (rear == size-1)
      return 1;
   else
      return 0;
}

int que_empty() //.......To check Queue is Empty
{
   if(front == rear == -1 || front == rear)
      return 1;
   else
      return 0;
}

void insert_AtRear(char job) //.......To Insert at Rear in DEQueue
{
   rear++;
   que[rear] = job;
}

void insert_AtFront(char job) //.......To Insert at Front in DEQueue
{ 
   que[front] = job;
   front--;
}
   
char del_AtFront() //.......To Delete From Front From DEQueue
{
   char ch;
 
   front++;
   ch = que[front];
 
   return ch;
}

char del_AtRear() //.......To Delete From Rear From DEQueue
{
   char ch;
 
   ch = que[rear];
   rear--;
 
   return ch;
}


void display() //.......To Display Queue.
{
   cout<<"\n\n Front--->  ";
   for(int i = front+1;i <= rear;i++)
      cout<<"  "<<que[i];
   
   cout<<"  <---Rear"; 
}


int main()
{
     int choice;
     char job,ans;
   
     do
     {
     cout<<"\n\n ** Menu **";
     cout<<"\n\n 1. Insert at Rear in DEQueue";
     cout<<"\n\n 2. Delete From Front in DEQueue";
     cout<<"\n\n 3. Insert at Front in DEQueue";
     cout<<"\n\n 4. Delete From Rear in DEQueue"; 
     cout<<"\n\n 5. Display DEQueue"; 
                   
   
     cout<<"\n\n Enter your choice:  ";                       
     cin>>choice;
   
     switch(choice)
     {
        case 1: cout<<"\n\n Enter the Job:  ";
      cin>>job;
        insert_AtRear(job);
        break;

        case 2: cout<<"\n\n Deleted Job:  "<<del_AtFront();
        break;

        case 3: cout<<"\n\n Enter the Job:  ";
      cin>>job;
        insert_AtFront(job);
        break;

        case 4: cout<<"\n\n Deleted Job:  "<<del_AtRear();
        break;

        case 5: display();
        break;
       
        default: cout<<"\n\n Invalid choice.....!!!";
     }
     cout<<"\n\n Do u wanna continue ?? (y/n) : ";
     cin>>ans;
     }while(ans == 'y');
   
     cout<<"\n\n";
     return 0;
}  

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