Introduction to Data Structures
practice.

The result of evaluating the postfix expression 5, 4, 6, +, *, 4, 9, 3, /, +, * is?

In linked list implementation of a queue, front and rear pointers are tracked. Which of these pointers will change during an insertion into EMPTY queue?

Which of the following piece of code has the functionality of counting the number of elements in the list?

Which of the following is false about a circular linked list?

The type of expression in which operator succeeds its operands is?

What is the result of the following operation?
Top (Push (S, X))

Which of the following statement(s) about stack data structure is/are NOT correct?

Which of the following properties is associated with a queue?

Given the Node class implementation, select one of the following that correctly inserts a node at the tail of the list.

public class Node
{
	protected int data;
	protected Node prev;
	protected Node next;
	public Node(int data)
	{
		this.data = data;
		prev = null;
		next = null;
	}
	public Node(int data, Node prev, Node next)
	{
		this.data = data;
		this.prev = prev;
		this.next = next;
	}
	public int getData()
	{
		return data;
	}
	public void setData(int data)
	{
		this.data = data;
	}
	public Node getPrev()
	{
		return prev;
	}
	public void setPrev(Node prev)
	{
		this.prev = prev;
	}
	public Node getNext
	{
		return next;
	}
	public void setNext(Node next)
	{
		this.next = next;
	}
}
public class DLL
{
	protected Node head;
	protected Node tail;
	int length;
	public DLL()
	{
		head = new Node(Integer.MIN_VALUE,null,null);
		tail = new Node(Integer.MIN_VALUE,null,null);
		head.setNext(tail);
		length = 0;
	}
}

In linked list each node contains a minimum of two fields. One field is data field to store the data second field is?

Consider yourself to be in a planet where the computational power of chips to be slow. You have an array of size 10.You want to perform enqueue some element into this array. But you can perform only push and pop operations .Push and pop operation both take 1 sec respectively. The total time required to perform enQueue operation is?

What is the functionality of the following piece of code? Select the most appropriate.

public void function(int data)
{
	int flag = 0;
	if( head != null)
	{
		Node temp = head.getNext();
		while((temp != head) && (!(temp.getItem() == data)))
		{
			temp = temp.getNext();
			flag = 1;
			break;
		}
	}
	if(flag)
		System.out.println("success");
	else
		System.out.println("fail");
}

How do you instantiate an array in Java?

What would be the asymptotic time complexity to insert an element at the second position in the linked list?

What is the output of the following Java code?

public class CircularQueue
{
	protected static final int CAPACITY = 100;
	protected int size,front,rear;
	protected Object q[];
	int count = 0;
 
	public CircularQueue()
	{
		this(CAPACITY);
	}
	public CircularQueue (int n)
	{
		size = n;
		front = 0;
		rear = 0;
		q = new Object[size];
	}
 
 
	public void enqueue(Object item)
	{
		if(count == size)
		{
			System.out.println("Queue overflow");
				return;
		}
		else
		{
			q[rear] = item;
			rear = (rear+1)%size;
			count++;
		}
	}
	public Object dequeue()
	{
		if(count == 0)
		{
			System.out.println("Queue underflow");
			return 0;
		}
		else
		{
			Object ele = q[front];
			q[front] = null;
			front = (front+1)%size;
			count--;
			return ele;
		}
	}
	public Object frontElement()
	{
		if(count == 0)
		return -999;
		else
		{
			Object high;
			high = q[front];
			return high;
		}
	}
	public Object rearElement()
	{
		if(count == 0)
		return -999;
		else
		{
			Object low;
			rear = (rear-1)%size;
			low = q[rear];
			rear = (rear+1)%size;
			return low;
		}
	}
}
public class CircularQueueDemo
{
	public static void main(String args[])
	{
		Object var;
		CircularQueue myQ = new CircularQueue();
		myQ.enqueue(10);
		myQ.enqueue(3);
		var = myQ.rearElement();
		myQ.dequeue();
		myQ.enqueue(6);
		var = mQ.frontElement();
		System.out.println(var+" "+var);
	}
}

What is the time complexity of searching for an element in a circular linked list?

Assume that the operators +,-, x are left associative and ^ is right associative. The order of precedence (from highest to lowest) is ^, x, +, -. The postfix expression for the infix expression a + b x c - d ^ e ^ f is?

The essential condition which is checked before insertion in a linked queue is?

Which of the following is the correct way to declare a multidimensional array in Java?

What is a memory efficient double linked list?