# Program to find average of all nodes in a Linked List

• Last Updated : 27 May, 2021

Given a singly linked list. The task is to find the average of all nodes of the given singly linked list.
Examples

```Input: 7->6->8->4->1
Output: 26
Average of nodes:
(7 + 6 + 8 + 4 + 1 ) / 5 = 5.2

Input: 1->7->3->9->11->5
Output: 6```

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Iterative Solution:

1. Initialise a pointer ptr with the head of the linked list and a sum variable with 0.
2. Start traversing the linked list using a loop until all the nodes get traversed.
3. Add the value of current node to the sum i.e. sum += ptr -> data .
4. Increment the pointer to the next node of linked list i.e. ptr = ptr ->next .
5. Divide sum by total number of node and Return the average.

Below is the implementation of the above approach:

## C++

 `// C++ implementation to find the average of``// nodes of the Linked List` `#include ``using` `namespace` `std;` `/* A Linked list node */``struct` `Node {``    ``int` `data;``    ``struct` `Node* next;``};` `// function to insert a node at the``// beginning of the linked list``void` `push(``struct` `Node** head_ref, ``int` `new_data)``{``    ``/* allocate node */``    ``struct` `Node* new_node = ``new` `Node;` `    ``/* put in the data */``    ``new_node->data = new_data;` `    ``/* link the old list to the new node */``    ``new_node->next = (*head_ref);` `    ``/* move the head to point to the new node */``    ``(*head_ref) = new_node;``}` `// Function to iteratively find the avg of``// nodes of the given linked list``float` `avgOfNodes(``struct` `Node* head)``{``    ``// if head = NULL``    ``if` `(!head)``        ``return` `-1;` `    ``int` `count = 0; ``// Initialize count``    ``int` `sum = 0;``    ``float` `avg = 0.0;` `    ``struct` `Node* current = head; ``// Initialize current``    ``while` `(current != NULL) {``        ``count++;``        ``sum += current->data;``        ``current = current->next;``    ``}` `    ``// calculate average``    ``avg = (``double``)sum / count;` `    ``return` `avg;``}` `// Driver Code``int` `main()``{``    ``struct` `Node* head = NULL;` `    ``// create linked list 7->6->8->4->1``    ``push(&head, 7);``    ``push(&head, 6);``    ``push(&head, 8);``    ``push(&head, 4);``    ``push(&head, 1);` `    ``cout << ``"Average of nodes = "` `<< avgOfNodes(head);` `    ``return` `0;``}`

## Java

 `// Java implementation to find the average of``// nodes of the Linked List``class` `GFG``{``    ` `/* A Linked list node */``static` `class` `Node``{``    ``int` `data;``    ``Node next;``};` `// function to insert a node at the``// beginning of the linked list``static` `Node push(Node head_ref, ``int` `new_data)``{``    ``/* allocate node */``    ``Node new_node = ``new` `Node();` `    ``/* put in the data */``    ``new_node.data = new_data;` `    ``/* link the old list to the new node */``    ``new_node.next = (head_ref);` `    ``/* move the head to point to the new node */``    ``(head_ref) = new_node;``    ``return` `head_ref;``}` `// Function to iteratively find the avg of``// nodes of the given linked list``static` `double` `avgOfNodes(Node head)``{``    ``// if head = null``    ``if` `(head == ``null``)``        ``return` `-``1``;` `    ``int` `count = ``0``; ``// Initialize count``    ``int` `sum = ``0``;``    ``double` `avg = ``0.0``;` `    ``Node current = head; ``// Initialize current``    ``while` `(current != ``null``)``    ``{``        ``count++;``        ``sum += current.data;``        ``current = current.next;``    ``}` `    ``// calculate average``    ``avg = (``double``)sum / count;` `    ``return` `avg;``}` `// Driver Code``public` `static` `void` `main(String args[])``{``    ``Node head = ``null``;` `    ``// create linked list 7.6.8.4.1``    ``head=push(head, ``7``);``    ``head=push(head, ``6``);``    ``head=push(head, ``8``);``    ``head=push(head, ``4``);``    ``head=push(head, ``1``);` `    ``System.out.println(``"Average of nodes = "` `+ avgOfNodes(head));``}``}``// This code is contributed by Arnab Kundu`

## Python3

 `# Python3 implementation to find the average of``# nodes of the Linked List``class` `newNode:` `    ``# Constructor to create a new node``    ``def` `__init__(``self``, data):``        ``self``.data ``=` `data``        ``self``.``next` `=` `None` `# function to insert a node at the``# beginning of the linked list``def` `push(node,data):``    ` `    ``''' allocate node '''``    ``if` `(node ``=``=` `None``):``        ``return` `(newNode(data))``    ` `    ``else``:``        ``node.``next` `=` `push(node.``next``, data)``        ``return` `node` `# Function to iteratively find the avg of``# nodes of the given linked list``def` `avgOfNodes(head):``    ` `    ``# if head = NULL``    ``if` `(head ``=``=` `None``):``        ``return` `-``1``    ` `    ``count ``=` `0` `# Initialize count``    ``sum` `=` `0``    ``avg ``=` `0.0` `    ``while` `(head !``=` `None``):``        ``count ``+``=` `1``        ``sum` `+``=` `head.data``        ``head ``=` `head.``next``    ` `    ``# calculate average``    ``avg ``=` `sum` `/` `count``    ``return` `avg` `# Driver Code` `# create linked list 7.6.8.4.1``head ``=` `newNode(``7``)``push(head, ``6``)``push(head, ``8``)``push(head, ``4``)``push(head, ``1``)``print``(``"Average of nodes = "``,avgOfNodes(head))` `# This code is contributed by``# Shubham Singh(SHUBHAMSINGH10)`

## C#

 `// C# implementation to find the average``// of nodes of the Linked List``using` `System;` `class` `GFG``{``    ` `/* A Linked list node */``public` `class` `Node``{``    ``public` `int` `data;``    ``public` `Node next;``};` `// function to insert a node at the``// beginning of the linked list``static` `Node push(Node head_ref,``                 ``int` `new_data)``{``    ``/* allocate node */``    ``Node new_node = ``new` `Node();` `    ``/* put in the data */``    ``new_node.data = new_data;` `    ``/* link the old list to the new node */``    ``new_node.next = (head_ref);` `    ``/* move the head to point to the new node */``    ``(head_ref) = new_node;``    ``return` `head_ref;``}` `// Function to iteratively find the avg of``// nodes of the given linked list``static` `double` `avgOfNodes(Node head)``{``    ``// if head = null``    ``if` `(head == ``null``)``        ``return` `-1;` `    ``int` `count = 0; ``// Initialize count``    ``int` `sum = 0;``    ``double` `avg = 0.0;` `    ``Node current = head; ``// Initialize current``    ``while` `(current != ``null``)``    ``{``        ``count++;``        ``sum += current.data;``        ``current = current.next;``    ``}` `    ``// calculate average``    ``avg = (``double``)sum / count;` `    ``return` `avg;``}` `// Driver Code``public` `static` `void` `Main(String []args)``{``    ``Node head = ``null``;` `    ``// create linked list 7.6.8.4.1``    ``head=push(head, 7);``    ``head=push(head, 6);``    ``head=push(head, 8);``    ``head=push(head, 4);``    ``head=push(head, 1);` `    ``Console.WriteLine(``"Average of nodes = "` `+``                           ``avgOfNodes(head));``}``}` `// This code is contributed by Rajput-Ji`

## Javascript

 ``
Output:
`Average of nodes = 5.2`

Time complexity : O(n)
Where n is equal to number of nodes.

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