Question

Create a MyQueue class in Java, similar to what we did when we created the MyStack class. Include a test class to show everything works correctly. Include all the methods mentioned in the power points that are normally included in a Queue.


This is MyStack class we did in a class. Have to make Queue class.

public class MyStack<E> {

private Node start;

private int currentCount;

public MyStack()

{

start = null;

currentCount = 0;

}

public void printStack()//available for testing, not O(1)

{

Node current = start;

while(current != null)

{

System.out.println(current.value);

current = current.next;

}

}

public void push(E val)//O(1)

{

Node newItem = new Node(val);

//if list is empty

if(start == null)

{

start = newItem;

}

else

{

newItem.next = start;

start = newItem;

}

currentCount++;

}

public E pop()//O(1)

{

if(start == null)//empty stack

{

return null;

}

else

{

E val = start.value;

start = start.next;

currentCount--;

return val;

}

}

public E top()//O(1)

{

if(start == null)//empty stack

{

return null;

}

else

{

E val = start.value;

return val;

}

}

public int size()//O(1)

{

return currentCount;

}

private class Node

{

E value;

Node next;

public Node(E v)

{

value = v;

next = null;//no node after this one

}

}

}

Answer 1

/*
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* and open the template in the editor.
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/**
*
* @author Vamsi
*/

class MyQueue<E> {

private Node start;

private int currentCount;

public MyQueue()

{

start = null;

currentCount = 0;

}

public void printQueue()//available for testing, not O(1)

{

Node current = start;

while(current != null)

{

System.out.println(current.value);

current = current.next;

}

}
//method to add element to queue at the end
public void Enqueue(E val)//O(1)

{

Node newItem = new Node(val);

//if list is empty

if(start == null)

{

start = newItem;

}

else

{
Node temp=start;

while(temp.next!=null)
{
temp=temp.next;
}

temp.next=newItem;
}

currentCount++;

}
//deleting first element
public E Dequeue()//O(1)

{

if(start == null)//empty stack

{

return null;

}

else

{

E val = start.value;

start = start.next;

currentCount--;

return val;

}

}

public E top()//O(1)

{

if(start == null)//empty stack

{

return null;

}

else

{

E val = start.value;

return val;

}

}

public int size()//O(1)

{

return currentCount;

}

private class Node

{

E value;

Node next;

public Node(E v)

{

value = v;

next = null;//no node after this one

}

}

}
public class QueueTester {
  
  
public static void main(String argv[])
{
//creating queue object
MyQueue<Integer> m = new MyQueue<Integer>();
//adding to queue
m.Enqueue(1);
m.Enqueue(2);
m.Enqueue(3);
m.Enqueue(4);
System.out.println("Queue:");
m.printQueue();
//deleting from queue
System.out.println("Deleted :"+m.Dequeue());
System.out.println("Deleted :"+m.Dequeue());
System.out.println("Queue:");
m.printQueue();
  
  
}
  
}

output:

run:
Queue:
1
2
3
4
Deleted :1
Deleted :2
Queue:
3
4
BUILD SUCCESSFUL (total time: 1 second)

//PLS give a thumbs up if you find this helpful, it helps me alot, thanks.