Explanation
This code implements a singly linked list in C++ and demonstrates inserting a node at the end:

Node Structure: Holds an integer data and a pointer next to the next node.
insertAtEnd Function:

Creates a new node with the given data and sets its next to nullptr.
If the list is empty (head is nullptr), sets the new node as the head.
Otherwise, traverses from the head to the last node (where next is nullptr).
Updates the last node's next to point to the new node.


printList Function: Traverses and prints the list for verification.
Main Function: Creates an empty list, inserts nodes (10, 20, 30), prints it, inserts 40 at the end, and prints again.

Output:
textLinked List before insertion: 10 -> 20 -> 30 -> NULL
Linked List after insertion: 10 -> 20 -> 30 -> 40 -> NULL
This matches the steps in the image: traverse to the last node, update its next from NULL to the new node, and set the new node's next to NULL.



#include <iostream>

// Define the Node structure
struct Node {
    int data;      // Data stored in the node
    Node* next;    // Pointer to the next node
};

// Function to insert a new node at the end of the linked list
void insertAtEnd(Node** head, int newData) {
    // Create a new node
    Node* newNode = new Node();
    newNode->data = newData;
    newNode->next = nullptr;  // Next pointer of new node is NULL (end of list)

    // If the list is empty, the new node becomes the head
    if (*head == nullptr) {
        *head = newNode;
        return;
    }

    // Traverse to the last node
    Node* last = *head;
    while (last->next != nullptr) {
        last = last->next;
    }

    // Change the next pointer of the last node to the new node
    last->next = newNode;
}

// Helper function to print the linked list
void printList(Node* head) {
    Node* temp = head;
    while (temp != nullptr) {
        std::cout << temp->data << " -> ";
        temp = temp->next;
    }
    std::cout << "NULL" << std::endl;
}

int main() {
    Node* head = nullptr;  // Initialize empty list

    // Insert some nodes
    insertAtEnd(&head, 10);
    insertAtEnd(&head, 20);
    insertAtEnd(&head, 30);

    // Print the list before inserting new node
    std::cout << "Linked List before insertion: ";
    printList(head);

    // Insert a new node at the end
    insertAtEnd(&head, 40);

    // Print the list after insertion
    std::cout << "Linked List after insertion: ";
    printList(head);

    // Clean up memory (optional for this example, but good practice)
    Node* current = head;
    while (current != nullptr) {
        Node* next = current->next;
        delete current;
        current = next;
    }

    return 0;
}