1. BY :
SADIA ZAR

2. Two Basic Operations in Queue
Enque : Inserting new element from rear end
Deque : Removing existing element from
front end
Front End
Rear End
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3. #include <iostream>
using namespace std;
class Queue
{
int* array,size,f,r,count;
public:
Queue();
void Enque(int value);
int Deque();
bool is_Empty();
bool is_Full();
};

4. Queue::Queue()
{
cout<<"Enter size : ";
cin>>size;
array=new int[size];
f=r=-1;
count=0;
}

5. void Queue::Enque(int value)
{
if(!is_Full())
{
array[++r]=value;
count++;
}
else
{
cout<<"nnOverFlow ! nn";
}
}

6. int Queue::Deque()
{
if(!is_Empty())
{
count--;
return array[++f];
}
else
{
cout<<"nnUnderFlow ! nn";
}
}

7. bool Queue::is_Empty()
{
return f==r==-1;
}
bool Queue::is_Full()
{
return count==size;
}

8. void main()
{
Queue obj;
obj.Enque(1);
obj.Enque(2);
obj.Enque(3);
obj.Deque();
}
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10. #include <iostream>
using namespace std;
class Node
{
int value;
Node*next;
friend class Queue;
public:
Node()
{
next=NULL;
}
};

11. class Queue
{
Node *first,*last;
public:
Queue()
{
first=last=NULL;
}
void Enque(int v);
bool is_Empty();
void Deque();
void Display();
};
first
last

12. void Queue::Enque(int v)
{
Node *n=new Node();
n->value=v;
if(first==NULL)
{
last=first=n;
}
else
{
last->next=n;
last=n;
}
}
DATA
NEXT

13. void Queue::Deque()
{
if(!is_Empty())
{
Node *temp=first;
first=first->next;
cout<<"nnThe data Dequeued is :
"<<temp->value<<endl;
delete temp;
}
}

14. bool Queue::is_Empty()
{
return first==NULL||last==NULL;
}

15. void Queue::Display()
{
Node *p = new Node;
p = first;
cout<<"nnQueue Elements are : nn";
while(p!=NULL)
{
cout<<p->value<<endl;
p = p->next;
}
}

16. Void main()
{
Queue Q;
Q.Enque(12);
Q.Enque(15);
Q. Deque();
Q .Display();
}
100
200
12
15
200
NULL
100
200
first
last
200