Question

Recycle is an entity which can hold at the most 100 integers. The chain enables the user to add and remove integers from both the ends i.e. front and rear.

Define a class ReCycle with the following details:

Class name	ReCycle
Data members/instance variables:
ele[ ]	the array to hold the integer elements
cap	stores the maximum capacity of the array
front	to point the index of the front
rear	to point the index of the rear
Methods / Member functions:
ReCycle (int max)	constructor to initialize the data cap = max, front = rear = 0 and to create the integer array.
void pushfront(int v)	to add integers from the front index if possible else display the message(“full from front”).
int popfront( )	to remove the return elements from front. If array is empty then return-999
void pushrear(int v)	to add integers from the front index if possible else display the message(“full from rear”).
int poprear( )	to remove and return elements from rear. If the array is empty then return-999.

1. Specify the class ReCycle giving details of the functions void pushfront(int) and int poprear( ). Assume that the other functions have been defined.
   The main( ) function and algorithm need NOT be written.
2. Name the entity described above and state its principle.

Answer 1

i.

class ReCycle
{
  void pushfront(int v)
  {
    if(front !=0)
      q[front--]=v;
    else
      System.out.println("FULL FROM FRONT");
  }
  int poprear()
  {
    if(front !=rear)
      return(q[rear--]);
    else
      return-999;
   }
}

ii. Entity is dequeue and works on the principle of FIFO