Question

Question No.4 [CLO 31 [5 marks] i. In the space provided, write appropriate data structure for following applications: a. An operating system is to process requests for computer resources by allocating the resource in the order in which they are requested b. A word processor to have f key that causes the preceding command to be re-displayed. Every time the user pressesſ key, the program shows the command that preceded the one currently displayed c. dictionary of words used by a spelling checker to be built and maintained ii. Implement a queue (First In First Out) using circular linked list with the constraint that you can keep only one Nodc* ptr to read/write data. Class Queue{ Private: Node* ptr; //Do not add any other data member in this class Public: Void Enqueue (int data);// You have to write this function int Dequeue (int data);// You have to write this function }

Answer 1

(a)Data structure = Queue
(b)Data structute = Stack
(c)Data structure = Linked List

(ii)

class Queue{
   private:
       Node* ptr;
   public:
       void Enqueue(int data){
           Node *newNode = new Node(data);
           if(ptr == NULL){
               newNode->next = newNode;
               ptr = newNode;
           }
           else{
               Node* current = ptr;
               while(current->next != ptr)current = current->next;
               current->next = newNode;
               newNode->next = ptr;
           }
       }
      
       int Dequeue(){
           int data = ptr->data;
           if(ptr->next == ptr){
               delete ptr;
               ptr = NULL;
               return data;
           }
           Node* current = ptr,*todelete = ptr;
           while(current->next != ptr)current = current->next;
           current->next = ptr->next;
           ptr = ptr->next;
           delete todelete;
           return data;
       }

}