Queue.pde

import java.util.*;

// Class for queue
class Queue 
{
  private int arr[];         // array to store queue elements
  private int front;         // front points to front element in the queue
  private int rear;          // rear points to last element in the queue
  private int capacity;      // maximum capacity of the queue
  private int count;         // current size of the queue
  
  // Constructor to initialize queue
  Queue(int size)
  {
    arr = new int[size];
    capacity = size;
    front = 0;
    rear = -1;
    count = 0;
  }

  // Utility function to remove front element from the queue
  public void dequeue()
  {
    // check for queue underflow
    if (isEmpty())
    {
    }

    System.out.println("Removing " + arr[front]);

    front = (front + 1) % capacity;
    count--;
  }

  // Utility function to add an item to the queue
  public void enqueue(int item)
  {
    // check for queue overflow
    if (isFull())
    {
    }

    System.out.println("Inserting " + item);

    rear = (rear + 1) % capacity;
    arr[rear] = item;
    count++;
  }

  // Utility function to return front element in the queue
  public int peek()
  {
    if (isEmpty()) 
    {
    }
    return arr[front];
  }

  // Utility function to return the size of the queue
  public int size()
  {
    return count;
  }

  // Utility function to check if the queue is empty or not
  public Boolean isEmpty()
  {
    return (size() == 0);
  }

  // Utility function to check if the queue is empty or not
  public Boolean isFull()
  {
    return (size() == capacity);
  }  
}