Thread: help with sorting a list :(

you mean something like this?

Code:

void swap(charNode **a, charNode **b, charNode *start) {
  charNode *temp, *preTemp;
  charNode *preA = pred(start->next, start);
  charNode *preB = pred(start, start);

  preTemp = preA;
  
  temp = *a;
  *a = *b;
  *preB = *preA;
  *b = temp;
  preB = preTemp;
  
}

*CRASH*

this is killing me :|

Code:

void swap(charNode **a, charNode **b, charNode *start) {
  charNode *temp, *preTemp;
  charNode *preA = pred(start->next, start);
  charNode *preB = pred(start, start);
  charNode* temp2 = (*preA).next;
  
    temp = *a;
   *a = *b;
   *b = temp;
	
	(*preA).next = (*preB).next;
	(*preB).next = temp2;
	 
  
}

*CRASH*

zx-1, i was just about to post the progress i made. The only problem was that the solution could only swap start and next node. Your solution however if i input any node it swaps it..hmm


i.e.:

Code:

void *swap(charNode **start, charNode *a, charNode *b)
{

      	 charNode *d = a->next->next->next;

      	 a->next = b->next;       
      	 b->next->next = b;       
      	 b->next= d;      
}

so i'm guessing its not possible to have a function like the one you have there that swaps the nodes and reconstructs the list? is it too complex? because i can swap the nodes if i know where they are but as soon as i try it on the middle node and the next for example it stuffs up the list.

i.e.:

works fine for swapping start and the next node.

Code:

	charNode *d = a->next->next;
      	charNode *head = start;
		a = b;       
      	b->next = head;
      	b->next->next=d;

this works fine for swapping the node after next and the one after next,next.

Code:

charNode *d = a->next->next->next;

      	 a->next = b->next;       
      	 b->next->next = b;       
      	 b->next= d;

but i cant seem to make a unified solution that does swapping regardless of the possition ?!?

yea agreed... it's better to actually swap the physical string than to modify the pointer