Difference Between Array and Linked List

A data element can be accessed easily in both data structures. The difference between array and linked list based on accessing the element is that in an array, random access, as well as sequential access, is possible, while in a linked list, only sequential access of data is possible, which is one of the disadvantages of using a linked list over an array data structure.

A linked list is a collection of nodes. A node consists of two parts data part and the pointer part. The last node of a linked list pointer contains a Null to indicate the end of the list. The presence of Null or “/0” marks the end of the list.

The time complexity to insert and delete an element is less than the time complexity for the same operations in the linked list. The difference between an array and linked list for the same operation is due to the random access of data in an array. While in a linked list, to insert or delete an element, one needs to sequentially traverse the list and then perform insertion and deletion.

The random access of data in an array is possible due to the index of an array. Whenever we store data in an array data structure, it gets stored sequentially, starting from the index zero and so on up to the last element. In order to access an element randomly, we need its array index.

In an array, the user needs to have knowledge of the size of the data beforehand. That is, before declaring an array, we need to know the size of the array we require. Let’s say we want to store one thousand elements. Then at the time of declaration of the array, we have to mention the size as one thousand. While in the case of a linked list, we do not need to specify the size beforehand. A linked list grows dynamically.