Advantage and Disadvantage of Linked List Over Array

Last Updated on April 25, 2023 by Abhishek Sharma

Two popular data structures used in programming are array and linked list. Both of these data structures have their own advantages and disadvantages, and choosing the right data structure depends on the use case. This article discusses the advantages and disadvantages of linked list over arrays. Before moving forward, let’s see a brief introduction to the linked list.

What is a Linked List?

A linked list is a popular data structure used in computer programming, which consists of a sequence of elements or nodes connected by links or pointers. In a linked list, each node contains two components: data and a reference to the next node in the sequence.

Types of Linked List

Now, let’s see the types of linked lists in detail.

1. Singly Linked List:
   Singly-linked lists are the simplest type of linked list, and each node contains a data component and a reference to the next node in the sequence. The last node in the sequence points to null, indicating the end of the list. Singly-linked lists can be efficiently traversed in one direction, from the beginning to the end.

   

2. Doubly or Two-Way Linked List:
   In a doubly linked list, each node contains a data component, a reference to the next node in the sequence, and a reference to the previous node in the sequence. This allows for efficient traversal of the list in both directions. The first node in the sequence has a null reference to the previous node, and the last node in the sequence has a null reference to the next node.

   

3. Circular Linked List:
   In a circular linked list, the last node in the sequence points to the first node, creating a circular link. This means that the list can be traversed indefinitely in a loop. Circular linked lists can be either singly linked or doubly linked.

   

4. Circular Doubly Linked List:
   A circular doubly linked list combines the features of both circular and doubly linked lists. Each node contains a data component, a reference to the next node in the sequence, and a reference to the previous node in the sequence. The last node in the sequence points to the first node, and the first node points to the last node.

   

5. Header Linked List:
   A header linked list is a special type of linked list that contains a dummy node at the beginning of the list. The dummy node does not contain any data but has a reference to the first node in the sequence. This makes it easier to manipulate the list and avoids special cases when inserting or deleting nodes at the beginning of the list.

   

Advantages of a Linked List over Arrays

Below are some advantages of Linked List over Arrays in programming, including:

1. Dynamic Size: One of the most significant advantages of linked list over arrays is that linked lists can grow or shrink dynamically during runtime. This means that the size of a linked list can be adjusted to accommodate new elements or remove existing elements without having to allocate or deallocate a fixed-size block of memory, as is the case with arrays.
2. Efficient Insertion and Deletion: Linked lists allow efficient insertion and deletion of elements at any position in the list, whereas arrays require shifting of elements when a new element is added or removed, which can be slow and inefficient for large arrays.
3. Memory Efficiency: Linked lists use memory more efficiently than arrays. In an array, all elements must be stored in contiguous memory locations, even if some of the elements are not used. In contrast, linked lists only allocate memory for the elements that are used, which can save memory in cases where the size of the data set is unknown or varies over time.
4. Easy Implementation of Abstract Data Types: Linked lists are easy to use and implement when implementing abstract data types such as stacks, queues, and trees. These data structures require frequent insertion and deletion of elements, which is a task in which linked lists are well-suited.
5. More Efficient Sorting: In some cases, linked lists can be more efficient for sorting algorithms than arrays. This is because linked lists do not require swapping elements like arrays, which can be time-consuming for large arrays.

In short, there are several advantages of linked list over arrays, such as dynamic size, efficient insertion and deletion, memory efficiency, easy implementation of abstract data types, and more efficient sorting in some cases.

Disadvantages of a Linked List over Arrays

While there are several advantages of linked list over arrays, they also have some disadvantages that need to be considered. Here are some disadvantages of linked list over arrays:

1. Random Access: Linked lists do not provide random access to elements like arrays do. To access an element in a linked list, we have to start at the beginning of the list and traverse the list until we find the desired element. This makes accessing individual elements in a linked list slower than in an array.
2. Extra Memory Usage: Linked lists require extra memory compared to arrays. Each element in a linked list requires a reference to the next element, which takes up additional memory space. In contrast, arrays only need memory to store the elements themselves.
3. More Complex Implementation: Implementing a linked list is more complex than implementing an array because it requires managing pointers and dynamically allocating memory. This complexity can lead to more bugs and errors in the code.

In short, there are several disadvantages of linked list over arrays, such as slower access times, extra memory usage, and more complex implementation.

Conclusion
So, in the above tutorial, we have discussed the advantages and disadvantages of linked list over arrays. Also, you can visit our practice coding questions on Linked List, which are curated by our expert mentors at PrepBytes.

FAQs

Here are some frequently asked questions on the advantages and disadvantages of linked list over arrays.

Q1: Can linked lists grow or shrink dynamically during runtime, unlike arrays?
Answer: Yes, linked lists can grow or shrink dynamically during runtime, making them more flexible and efficient when working with large or variable-sized data sets.

Q2: Can linked lists provide random access to elements like arrays?
Answer: No, linked lists do not provide random access to elements like arrays do. To access an element in a linked list, we have to start at the beginning of the list and traverse the list until we find the desired element.

Q3: Do linked lists require extra memory compared to arrays?
Answer: Yes, linked lists require extra memory compared to arrays. Each element in a linked list requires a reference to the next element, which takes up additional memory space.

Q4: Can traversing a linked list result in more CPU cache misses than accessing an array?
Answer: Yes, traversing a linked list can result in more CPU cache misses than accessing an array. In a linked list, each element can be stored in a different memory location, which can result in more cache misses and slower performance.

Q5: Can linked lists save memory in cases where the size of the data set is unknown or varies over time?
Answer: Yes, linked lists can save memory in cases where the size of the data set is unknown or varies over time because they only allocate memory for the elements that are used, unlike arrays, which allocate memory for all elements, even if some are not used.

Q6: Are linked lists better suited for dynamic data structures than arrays?
Answer: Yes, linked lists are better suited for dynamic data structures than arrays because they can grow or shrink dynamically during runtime, whereas arrays have a fixed size.