Re: [Dev-C++] Linked List...Again

[Michal M. <mol...@se...>]

Dne 9.5.2011 17:44, Jordan Burnam napsal(a):
> Node *Head;
> Node *Curr;
> Node *Last;
>
>
>
>
> numstep = 5;
>
>
> for( int i = 1; i <= numstep; i++)
> {
> (*Head).ptr_next_node = NULL;

Here you are using Head but you haven't allocated it anywhere. There 
must be Head = new Node; before the for loop.

> if((*Head).ptr_next_node == NULL)

What is this good for? You just set it to NULL on previous line.

> {
>
> Last = Head;
> Curr = Head;
> cout << " The " << i << "step, please enter the text for this setp and
> then press enter: ";
> cin >> (*Head).steppy.Instruction;
> (*Head).steppy.stepNum = i;
> (*Head)ptr_next_node = new Node;

Probably missing . here. Note that (*x).y is the same as x->y in this case.

> Curr = (*Head).ptr_next_node;
>
> }

Here you probably intended "else". However it won't work because the if 
condition will always be true as explained above.

> cout << "The " << i << " step, please enter the text for this step and
> then press enter: ";
> cin >> (*Curr).steppy.Instruction;
> (*Curr).steppy.stepNum = i;
> (*Curr).ptr_next_node = new Node;
> Last = Curr;
> Curr = (*Curr).ptr_next_node;

===================================
  Node *Head;
  Node *Curr;

  numstep = 5;

  Curr = Head = new Node;
  Head->ptr_next_node = NULL;
  for( int i = 1; i <= numstep; i++)
  {
    cout << " The " << i
<< "step, please enter the text for this setp and then press enter: ";
    cin >> Curr->steppy.Instruction;
    Curr->steppy.stepNum = i;
    Curr->ptr_next_node = i == numstep ? NULL : new Node;
    Curr = Curr->ptr_next_node;
   }


  Curr = Head;
  while(Curr) {
cout << Curr->steppy.stepNum << " " << Curr->steppy.Instruction << endl;
   Curr = Curr->ptr_next_node;
  }