A linked list is an important topic to understand while preparing for technical interviews, and it may be used to answer a variety of problems. To solve and answer complex questions, it is necessary to have a profound understanding of the fundamental principles.
This blog will discuss a fundamental but significant topic, i.e., the differences between a singly linked list and a doubly linked list.
A unidirectional linked list containing a set of ‘N’ nodes that can be traversed from the first node to the last node is called a singly linked list. Its node consists of two parts, data and a pointer containing the address of the next node.
For example,
Doubly Linked List
A linked list containing a set of ‘N’ nodes that can be traversed in both directions, i.e., forward and backward, is termed as a doubly-linked list. Each node of a Doubly Linked List consists of three parts, data, and two pointers, one containing the address of the next node and the other having the address of the previous node.
For example,
Difference between Singly Linked List and Doubly Linked List
Let us look at a few key differences between a singly linked list and a doubly linked list.
Key
Singly Linked List
Doubly Linked List
Components
Its node consists of two parts, one for storing the data and the other containing the pointer that holds the address of the next node.
Its node consists of three parts, one for storing the data and the other two containing pointers that hold the address of the previous and the following nodes.
Traversal
It can be traversed only in one direction, i.e., the forward direction.
It can be traversed in both directions, i.e., forward as well as backward.
Memory
It utilizes less memory as it uses only one pointer to store the address of the next node.
It utilizes more memory as it uses two pointers to store the addresses of the next and the previous nodes.
Performance
It lacks in terms of performance but utilizes less memory.
It provides better performance but uses more memory which can be considered to be a limitation.
Complexity
The time complexity to insert or delete an element at a particular position (pointer to that position is given to us) is given by O(N), where N is the total number of nodes in the linked list.
The time complexity to insert or delete an element in a doubly-linked list, at a position whose pointer is given, is constant, i.e., O(1).
Applications
A singly linked list is used to implement stacks and queues. Any FIFO structure can be implemented using a singly linked list, and message delivery on a network is also based on this concept.
It is used to implement data structures like heaps and binary trees. It is also used to implement backward and forward navigation of visited web pages, and to implement undo and redo in many applications.
What is the Key Difference between a Singly-Linked List and a Doubly-Linked List?
A Singly-Linked List contains a pointer to only its next node whereas a Doubly-Linked List contains a pointer to both its next as well as previous node.
What is the stopping condition of the quick sort algorithm?
Like the Quicksort() function, the Partition() function takes an array and its size. In this function, we first check that the array size is larger than 1; this is the stopping condition since an array of size 1 is, by definition, sorted.
How does quicksort for linked lists work?
Quicksort algorithm is a divide and conquers algorithm; it divides the list into smaller sublists, then takes a pivot element and sorts it into higher and lower groups, and then nests the quick sort into newly formed groups till the goal is achieved.
What is the advantage of doubly linked list over singly linked list?
The advantages of using a doubly linked list over a singly linked list include the ability to efficiently traverse the list in both directions, faster deletion of nodes, and increased flexibility in certain programming applications.
Conclusion
So, this blog discussed the difference between a singly linked list and a doubly linked list. To learn more topics like Linked List, Graphs, Trees, head over right now toCoding Ninjas Studio and crack your interviews like a Ninja!
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