#include <iostream>
using namespace std;

struct Node
{
   int data;
   Node* next;
};

void printList( Node* start )
{
   while ( start != NULL  )
   {
      //print current element
      cout << start -> data <<endl;
      //advance down the list
      start = start -> next;
   }
   start = NULL;
}

//PreCondition:
//start is an undetermined (even blank) sized linked list
//nodeToAdd is already initialized
//PostCondition:
//Will return the start of a linked list with at least 1 element
Node* addAtBack( Node* start, Node* nodeToAdd )
{
   //If list is empty
   if ( NULL == start )
   { 
      //make sure starts next pointer is null
      nodeToAdd -> next = NULL;
      //return nodeToAdd 
      return nodeToAdd; 
   }
   //If list is not empty
   else
   {
      //iterate down to last element
      Node* temp = start;
      while ( temp -> next != NULL )
      {
         temp = temp -> next;  //advance 1 node down list
      }
      //temp is now pointing to the last element in the list
      //set list->next pointer to point to temp 
      temp -> next = nodeToAdd;
      return start;
   }
}

int main()
{
   Node* head = NULL;  //create holder for start of list
   head = new Node();  //allocate space for node, return ptr
   head -> data = 1;   //dereference head, use dot op. and assign 1
   head -> next = NULL;
//   printList ( head ); 
   
   Node* temp = new Node(); // create a temp pointer
   temp -> data = 2;
   temp -> next = NULL;

   head = addAtBack( head, temp );

   printList( head );
}