Singly Linked List

Preview

1. What is a singly linked list and how does it differ from other types of lists?
2. What advantage does a singly linked list have over an array when it comes to insertion and deletion operations?
3. What are the basic operations that can be performed on a singly linked list, and how do they affect the structure of the list?
4. What are some common algorithms that can be used to manipulate singly linked lists, such as traversal or reversing the list?
5. What are some common use cases for singly linked lists, and how can they be applied in software development?

Explain

A singly linked list is a linear data structure where each element in the list is stored as a node, consisting of two parts: data and a reference (or a pointer) to the next node in the list. The last node in the list points to null to indicate the end of the list.

Here is an example of a singly linked list:

Head –> [5 | Next –>] –> [10 | Next –>] –> [15 | Next –>] –> [20 | Next –>] –> Null

In this example, we have a linked list with four nodes, where the data values of the nodes are 5, 10, 15, and 20. The first node in the list, the head, points to the first node with the data value of 5. The next pointer of the first node points to the second node with the data value of 10, and so on, until the last node with the data value of 20, which points to null.

Singly linked lists are commonly used to implement other data structures, such as stacks, queues, and hash tables, as well as for dynamic memory allocation in programming languages.

Keypoint

1. Singly Linked List is a data structure that consists of a sequence of nodes.
2. Each node contains two fields: data and a pointer to the next node in the sequence.
3. The first node in the sequence is called the head node, and the last node is called the tail node.
4. Singly Linked List supports traversal in one direction only, from the head to the tail.
5. Operations that can be performed on Singly Linked List include insertion, deletion, and searching for an element in the List.
6. Singly Linked List can be used to implement various algorithms such as a stack, a queue, and a hash table.
7. Singly Linked List is a dynamic data structure, and its size can be adjusted during runtime as required.
8. Singly Linked List has a lower memory requirement than an array but requires more time for searching or retrieval of an element.

Review

1. What is a singly linked list?
   Answer: A singly linked list is a linear data structure consisting of a sequence of nodes, where each node contains a value and a pointer to the next node in the sequence.

2. What is the time complexity for inserting a node at the beginning of a singly linked list?
   Answer: The time complexity for inserting a node at the beginning of a singly linked list is O(1) as it involves updating just one pointer to point to the new node.

3. How do you remove the last node from a singly linked list?
   Answer: To remove the last node from a singly linked list, you need to traverse the list until you reach the second last node, then update its next pointer to null.

4. What is the difference between a singly linked list and a doubly linked list?
   Answer: A singly linked list only has a pointer to the next node in the sequence, while a doubly linked list has pointers to both the previous and next nodes in the sequence.

5. What is the advantage of using a singly linked list compared to an array?
   Answer: The advantage of using a singly linked list is that it can be easily modified by inserting or deleting nodes without requiring the entire list to be shifted, which is time-consuming and inefficient for arrays.