Question

11.)

Suppose you have a linked list of Node objects from the Textbook Collections Framework and currentNode has been initialized to refer to the head node in the list. Which of these statements needs to appear in a loop that goes through the list's items one-by-one?

Select one:

a. currentNode++

b. currentNode = currentNode.next

c. currentNode = previous()

d. currentNode += 1

e. currentNode = next()

12.) A singly linked node contains which of these fields?

Select one:

a. data item, link to next node, and link to previous node

b. link to next node only

c. an empty link

d. data item only

e. data item and link to next node

13.) Which of these describes how an item in a linked data structure is accessed?

Select one:

a. immediately accessed via a base address and offset

b. accessed by starting at one end and following the links until the item is reached

c. immediately accessed via an index

d. accessed by hashing its value

e. accessed via a binary search

15.) Which of these is done to insert an item into an array that grows?

Select one:

a. all of these

b. shift the items from the target index position to the logical end of the array one slot towards the physical end of the array

c. increment the logical size of the array by 1

d. assign the new item to the target index position

e. check for available space before attempting an insertion and increase the physical size of the array if necessary

Answer 1

Linked List questions

Introduction for better understanding:

Linked List is a linear data structure where its elements are linked using pointers.

Each record of a linked list is known as an element/node.
Each node in a list has at least two parts:

1) data/value/cargo/payload etc.
2) Pointer/link/reference to the next node

Linked list is represented using a pointer to the first node of the list (called the head of the list). Whereas, the remaining part of the list after the head or the last node is called “tail”.

In C, we represent a node using structures. In Java or C#, we represent LinkedList Node as separate classes.

class LinkedList

{

Node head; // head of the list

  

        class Node {

        int data;

        Node next;

  

        // create a new node

Node (int d)

{

data = d;

}

}

}

Question number 11 in the given set of questions:

11) Suppose you have a linked list of Node objects from the Textbook Collections Framework and currentNode has been initialized to refer to the head node in the list. Which of these statements needs to appear in a loop that goes through the list's items one-by-one?

Select one:

a. currentNode++

b. currentNode = currentNode.next

c. currentNode = previous()

d. currentNode += 1

e. currentNode = next()

Solution:

Option b is the correct answer.

Explanation:

To search in element in a Linked list or to print the elements in the list, we do traversing from one-by-one in the list starting from head node to remaining nodes. This can be achieved by assigning current node in the list to next link reference(starting from head).

As given in the question, Current node is initialized to the head. We can proceed further through list using “currentNode = currentNode.next “assignment statement in a loop.

Other Options are wrong because:

a) currentNode++ --only for incrementing current node by 1. It does not allow you to traverse through the list

c) currentNode = previous()—This is not how we traverse through the list in a loop. It is syntactically wrong.

d) currentNode += 1-- only for incrementing current node by 1. It does not allow you to traverse through the list

e) currentNode = next()--This is not how we traverse through the list in a loop. It is syntactically incorrect.

Question number 12 in the given set of questions:

12) A singly linked node contains which of these fields?

Select one:

a. data item, link to next node, and link to previous node

b. link to next node only

c. an empty link

d. data item only

e. data item and link to next node

Solution:

Option e is the correct answer.

Explanation:

Singly linked list contains elements or nodes which have a data items as well as next pointer, which links to the next node in list of nodes of a linked list.

Other Options are wrong because:

As given in the introduction of a linked list, remaining options are not applicable for the question.

Question number 13 in the given set of questions:

13) Which of these describes how an item in a linked data structure is accessed?

Select one:

a. immediately accessed via a base address and offset

b. accessed by starting at one end and following the links until the item is reached

c. immediately accessed via an index

d. accessed by hashing its value

e. accessed via a binary search

Solution:

Option b is the correct answer.

Explanation:

Here, option b is the right answer, which is a major drawback of Linked list. In linked list, random access is not possible. An element can be accessed only by traversing sequentially starting from the first node (head).

Other Options are wrong because:

As memory allocation for the linked list is dynamic and non-contiguous it makes it difficult to find an element using other techniques such as binary search. So we cannot efficiently access an element using the specified techniques. Also they are not applicable.

Question number 13 in the given set of questions:

15) Which of these is done to insert an item into an array that grows?

Select one:

a. all of these

b. shift the items from the target index position to the logical end of the array one slot towards the physical end of the array

c. increment the logical size of the array by 1

d. assign the new item to the target index position

e. check for available space before attempting an insertion and increase the physical size of the array if necessary

Solution:

Option a is the correct answer.

Explanation:

A Dynamic array grows if we want to insert an item and there is no more space left for the new item.

So a simple dynamic array can be created with size larger than the number of elements required immediately. The elements of the dynamic array are stored contiguously at the start of the underlying array where remaining positions are reserved for future use or unused. Therefore, elements can be added at the end of a dynamic array by using these unused positions, until they are consumed.

But, when all positions are consumed, and if we want to add one more element, the underlying array size is increased.

Also, If we want to insert an item element to the array, you can use any of the approaches given below.

• Using a new array larger than the original.
• Using ArrayList as an intermediate structure.
• Shifting the elements to accommodate the new element.

For instance, If the array size is n, you can create a new array with size n+1 for future use, if we want to add one element. Then , copy the original array of n elements into the new array. Insert new item at n+1 location.

So, all the options are correct for this question. So answer is “all of these”