Add two Numbers Represented by Linked Lists in C++

#include <iostream>

// Definition for singly-linked list.
struct ListNode {
    int val;
    ListNode* next;
    ListNode(int x) : val(x), next(nullptr) {}
};

// Function to add two numbers represented by linked lists
ListNode* addTwoNumbers(ListNode* l1, ListNode* l2) {
    ListNode* dummy = new ListNode(0); // Create a dummy node to start the result list
    ListNode* current = dummy; // Initialize the current pointer to the dummy node
    int carry = 0; // Initialize the carry value to 0

    while (l1 || l2 || carry) {
        int sum = carry;
        if (l1) {
            sum += l1->val;
            l1 = l1->next;
        }
        if (l2) {
            sum += l2->val;
            l2 = l2->next;
        }

        carry = sum / 10; // Calculate the carry for the next iteration
        current->next = new ListNode(sum % 10); // Add a new node with the remainder to the result
        current = current->next; // Move the current pointer forward
    }

    return dummy->next; // Return the result linked list (skip the dummy node)
}

// Function to print a linked list
void printList(ListNode* head) {
    ListNode* current = head;
    while (current) {
        std::cout << current->val << " ";
        current = current->next;
    }
    std::cout << std::endl;
}

int main() {
    // Example usage
    ListNode* l1 = new ListNode(2);
    l1->next = new ListNode(4);
    l1->next->next = new ListNode(3);

    ListNode* l2 = new ListNode(5);
    l2->next = new ListNode(6);
    l2->next->next = new ListNode(4);

    std::cout << "Input lists: " << std::endl;
    printList(l1);
    printList(l2);

    ListNode* result = addTwoNumbers(l1, l2);

    std::cout << "Sum of the numbers represented by linked lists: " << std::endl;
    printList(result);

    // Clean up memory
    delete l1;
    delete l2;
    delete result;

    return 0;
}