Arrays Linked Lists Questions Medium
An array is a data structure that stores a fixed-size sequence of elements of the same type. It is a contiguous block of memory where each element can be accessed using an index. The elements in an array are stored in a specific order and can be accessed directly by their index position.
On the other hand, a linked list is a data structure that consists of a sequence of nodes, where each node contains a value and a reference (or link) to the next node in the sequence. Unlike an array, the elements in a linked list are not stored in contiguous memory locations. Instead, each node in the linked list contains a reference to the next node, forming a chain-like structure.
The main difference between an array and a linked list lies in their underlying implementation and the way elements are accessed. In an array, elements can be accessed in constant time O(1) by using their index, as the memory locations are contiguous. However, inserting or deleting elements in an array requires shifting the subsequent elements, resulting in a time complexity of O(n).
In contrast, linked lists allow for efficient insertion and deletion operations, as they only require updating the references of the adjacent nodes. However, accessing an element in a linked list requires traversing the list from the beginning, resulting in a time complexity of O(n) in the worst case.
Additionally, arrays have a fixed size determined at the time of declaration, while linked lists can dynamically grow or shrink as elements are added or removed.
In summary, arrays provide efficient random access to elements but have limitations in terms of dynamic resizing and insertion/deletion operations. Linked lists, on the other hand, offer flexibility in terms of resizing and efficient insertion/deletion operations but have slower access times.