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

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
```

## Recommended: Please try your approach on {IDE} first, before moving on to the solution.

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 `

## 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 `

Output:

```Average of nodes = 5.2
```

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

My Personal Notes arrow_drop_up Check out this Author's contributed articles.

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.

Article Tags :
Practice Tags :

1

Please write to us at contribute@geeksforgeeks.org to report any issue with the above content.