Queue Implementation Using Array & Linked List

Queue Implementation Using Array & Linked List

• 1.
  BY : SADIA ZAR
• 2.
  Two Basic Operationsin Queue Enque : Inserting new element from rear end Deque : Removing existing element from front end Front End Rear End 0 1 2 3 4 5 6
• 3.
  #include <iostream> using namespacestd; 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; } boolQueue::is_Full() { return count==size; }
• 8.
  void main() { Queue obj; obj.Enque(1); obj.Enque(2); obj.Enque(3); obj.Deque(); } 12 3 0 1 2 3 4 5 6
• 10.
  #include <iostream> using namespacestd; class Node { int value; Node*next; friend class Queue; public: Node() { next=NULL; } };
• 11.
  class Queue { Node *first,*last; public: Queue() { first=last=NULL; } voidEnque(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<<"nnThedata 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