Linked List vs Array

Last Updated : 1 Jun, 2026

Arrays and Linked Lists are two of the most commonly used linear data structures for storing collections of data. Although both are used to store multiple elements, they differ in memory allocation, access methods, and performance characteristics.

Arrays store elements in contiguous memory locations.
Linked Lists store elements in separate nodes connected through references.
The choice between them depends on the application's requirements for memory usage and operation efficiency.

Array

An Arrays is a linear data structure that stores elements of the same data type in contiguous memory locations. Since the memory addresses are sequential, any element can be accessed directly using its index.

Stores elements in contiguous memory locations.
Supports direct access through indexing.
Generally has a fixed size after creation.

Data storage scheme of an array

C++

#include <iostream>
using namespace std;

int main() {
    int arr[] = {10, 20, 30, 40, 50};

    cout << arr[2];

    return 0;
}

Output

Explanation: The element at index 2 is accessed directly from the array, so the value 30 is printed in O(1) time.

Linked List

Linked list is a linear data structure consisting of nodes, where each node contains data and a reference to the next node. Unlike arrays, nodes are not stored in contiguous memory locations.

Elements are stored in separate memory locations.
Each node contains data and a reference to the next node.
The size can grow or shrink dynamically.

Linked-List representation

C++

#include <iostream>
using namespace std;

class Node {
public:
    int data;
    Node* next;

    Node(int value) {
        data = value;
        next = NULL;
    }
};

int main() {
    Node* first = new Node(10);
    Node* second = new Node(20);

    first->next = second;

    cout << first->data << endl;
    cout << first->next->data;

    return 0;
}

Output

10
20

Explanation: The first node stores 10 and points to the second node storing 20, creating a simple linked list with two nodes.

Array Vs Linked List

Feature	Array	Linked List
Memory Storage	Elements are stored in contiguous memory locations.	Nodes are stored in non-contiguous memory locations.
Access Time	Direct access using index in O(1) time.	Sequential access requiring O(n) time.
Insertion	Insertion is slower due to element shifting.	Insertion is faster as only pointers are updated.
Deletion	Deletion requires shifting remaining elements.	Deletion is efficient with pointer adjustments.
Size	Generally fixed after creation.	Can grow or shrink dynamically.
Memory Usage	Requires less memory overhead.	Requires extra memory for pointers.
Cache Performance	Better cache locality and faster traversal.	Poor cache locality due to scattered nodes.
Implementation	Simple and easy to implement.	More complex because of pointer management.
Searching	Faster when index is known.	Requires traversal from the beginning.
Best Use Case	Suitable for frequent access operations.	Suitable for frequent insertion and deletion operations.

Advantages of Linked List over arrays

Efficient Insertion and Deletion: Linked Lists allow insertion and deletion operations without shifting elements. If the position is known, these operations can be performed in O(1) time.
Dynamic Size: Unlike arrays, Linked Lists can grow or shrink during runtime without requiring memory reallocation, making them suitable when the number of elements is unknown.
Easy Implementation of Queue and Deque: Linked Lists provide efficient insertion and deletion at both ends, making the implementation of Queues and Deques simple and straightforward.
Useful for Circular Structures: Circular Linked Lists are ideal for applications such as CPU Round Robin Scheduling, where continuous traversal and quick insertion/deletion are required.

Advantages of Arrays over Linked List

Random Access. : We can access ith item in O(1) time (only some basic arithmetic required using base address). In case of linked lists, it is O(n) operation due to sequential access.
Cache Friendliness : Array items (Or item references) are stored at contiguous locations which makes array cache friendly (Please refer Spatial locality of reference for more details)
Easy to use : Arrays are relatively very easy to use and are available as core of programming languages
Less Overhead : Unlike linked list, we do not have any extra references / pointers to be stored with every item.

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