C++ program to simulate deque with functions to add and delete elements from either end of the deque

Problem Statement:-

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

Code:-

	//Progrom to illustrate double ended queue using array.
	#include<iostream>
	//#include
	//#include
	using namespace std;
	#define SIZE 5
	// ERROR HANDLINH NOT DOne
	// program is not working correct.
	//
	class dequeue
	{
	int a[10],front,rear,count;
	public:
	dequeue();
	void add_at_beg(int);
	void add_at_end(int);
	void delete_fr_front();
	void delete_fr_rear();
	void display();
	};
	dequeue::dequeue()
	{
	front=-1;
	rear=-1;
	count=0;
	}
	void dequeue::add_at_beg(int item)
	{
	int i;
	if(front==-1)
	{
	front++;
	rear++;
	a[rear]=item;
	count++;
	}
	else if(rear>=SIZE-1)
	{
	cout<<"\nInsertion is not possible,overflow!!!!";
	}
	else
	{
	for(i=count;i>=0;i--)
	{
	a[i]=a[i-1];
	}
	a[i]=item;
	count++;
	rear++;
	}
	}
	void dequeue::add_at_end(int item)
	{
	if(front==-1)
	{
	front++;
	rear++;
	a[rear]=item;
	count++;
	}
	else if(rear>=SIZE-1)
	{
	cout<<"\nInsertion is not possible,overflow!!!";
	return;
	}
	else
	{
	a[++rear]=item;
	}
	}
	void dequeue::display()
	{
	for(int i=front;i<=rear;i++)
	{
	cout<<a[i]<<" "; }
	}
	void dequeue::delete_fr_front()
	{
	if(front==-1)
	{
	cout<<"Deletion is not possible:: Dequeue is empty";
	return;
	}
	else
	{
	if(front==rear)
	{
	front=rear=-1;
	return;
	}
	cout<<"The deleted element is "<<a[front];
	front=front+1;
	}
	}
	void dequeue::delete_fr_rear()
	{
	if(front==-1)
	{
	cout<<"Deletion is not possible:Dequeue is empty";
	return;
	}
	else
	{
	if(front==rear)
	{
	front=rear=-1;
	}
	cout<<"The deleted element is "<< a[rear];
	rear=rear-1;
	}
	}
	int main()
	{
	int c,item;
	dequeue d1;
	do
	{
	cout<<"\n\n****DEQUEUE OPERATION****\n";
	cout<<"\n1-Insert at beginning";
	cout<<"\n2-Insert at end";
	cout<<"\n3_Display";
	cout<<"\n4_Deletion from front";
	cout<<"\n5-Deletion from rear";
	cout<<"\n6_Exit";
	cout<<"\nEnter your choice<1-4>:";
	cin>>c;
	switch(c)
	{
	case 1:
	cout<<"Enter the element to be inserted:";
	cin>>item;
	d1.add_at_beg(item);
	break;
	case 2:
	cout<<"Enter the element to be inserted:";
	cin>>item;
	d1.add_at_end(item);
	break;
	case 3:
	d1.display();
	break;
	case 4:
	d1.delete_fr_front();
	break;
	case 5:
	d1.delete_fr_rear();
	break;
	case 6:
	exit(1);
	break;
	default:
	cout<<"Invalid choice";
	break;
	}
	}while(c!=7);
	return 0;
	}

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Output:-