Reverse a linked list

reverse_linked_list_iterative.cpp

// Solved problem: https://leetcode.com/problems/reverse-linked-list/

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode(int x) : val(x), next(NULL) {}
 * };
 */
#include <iostream>
using namespace std;

class Solution {
public:
    void PrintList(ListNode* list)
    {
        while (list != NULL)
        {
            cout << list->val << " -> ";
            list = list->next;
        }
        cout << "NULL" << endl;
    }
    
    ListNode* reverseList(ListNode* head) {
        
        if (head == NULL || head->next == NULL)
            return head;
        
        ListNode* current = head->next;
        ListNode* newNode = head;
        newNode->next = NULL;
        
        while (current != NULL)
        {       
            ListNode* newNodeTemp = newNode;
            
            newNode = new ListNode(current->val); //Create node to add to the beginning of list
            newNode->next = newNodeTemp; //Attach the result reverted list to the new beginning node

            PrintList(newNode);

            current = current->next; //Move to the next node
        }
        
        cout << "Result:" <<endl;
        PrintList(newNode);
        
        return newNode;
    }
};

https://leetcode.com/problems/reverse-linked-list/

Complexity: O(n-1)