#include <iostream>
using namespace std;

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

const int LIST_LENGTH = 15;

void PrintList( Node* startOfList );
void BuildAList( Node* headPtr, int NumberOfNodes );
Node* BuildListFromScratch( int NumberOfNodes );
Node* AddAtBack( Node* headPtr, int value );



int main()
{
   Node* headPtr = NULL;// BuildListFromScratch( LIST_LENGTH );
   headPtr = AddAtBack ( headPtr, 55 );
   BuildAList( headPtr, LIST_LENGTH );
   PrintList ( headPtr );
}

Node* AddAtBack( Node* headPtr, int value )
{
   //Create a new node
   Node* Last = new Node;
   //Set new nodes payload to value
   Last -> payload = value ;
   //set new nodes next pointer to null
   Last -> next = NULL;

   //1 Determine if headPtr is null
   //2 If headPtr is null
   if ( headPtr == NULL )
   {
   //3 Return newly created node
      return Last;
   }
   //4 If headPtr is not null
   else
   { 
     // 5 Create tempPtr, set equal to headPtr
     Node* tempPtr = headPtr;
       
     // 6 move tempPtr down list
     // 6 until tempPtr -> next equals null
     while ( tempPtr -> next != NULL )
     {
        tempPtr = tempPtr -> next;
     }
     // 7 M  Make tempptrs next ptr equal the newly created Ptr
     tempPtr -> next = Last;  
 
     //8 Return headPtr;
     return headPtr;
} 



} 

Node* BuildListFromScratch( int Length )
{
   Node* headPtr = new Node;
   headPtr -> payload = 1;
   headPtr -> next = NULL; 
   BuildAList( headPtr, Length ); 
   return headPtr;
}

// Builds a Linked List
// Precondition: headPtr refers to a linked list with at least one node
// Postcondition: Builds a linked list NumberOfNodes in length
void BuildAList( Node* headPtr, int NumberOfNodes )
{
   Node* workingPtr;
   Node* trailingPtr = headPtr;
   for ( int i = 2; i < NumberOfNodes + 1; i++ )
   {
      workingPtr = new Node;
      workingPtr -> payload = i;
      workingPtr -> next = NULL;
      trailingPtr -> next = workingPtr;
      trailingPtr = workingPtr;
   }
}

void PrintList( Node* startOfList )
{
   while ( startOfList != NULL )
   {
      cout << startOfList -> payload << endl;
      startOfList = startOfList -> next;
   }
}