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:

Initialise a pointer ptr with the head of the linked list and a sum variable with 0.
Start traversing the linked list using a loop until all the nodes get traversed.
Add the value of current node to the sum i.e. sum += ptr -> data .
Increment the pointer to the next node of linked list i.e. ptr = ptr ->next .
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 <bits/stdc++.h> 
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

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

C++

Java

C#

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