Thread: i can't seem to understand the logic behind linked lists :|

noo. the reason why i said, when u interate through each node u will check for the last node.The way u can find is that the last node next should be null. So when u check for loc->next is equal to null u will come to know that u reached end of the node. and then u can follow with appending a new node.

ssharish2005

Originally Posted by Axel

and here i've shortended to code even more, i guess it's easier to understand:

Code:

  	for (prev=NULL; loc != NULL; loc = loc->next)
      	{
			prev = loc;
      	}
      	
    	prev->next = temp;

this is not quite rite ...

say u have

Code:

"Panda" -> NULL

on the first iteration, loc = *start yes?
and then you assign prev to loc...

Code:

prev = loc;

and after that, the for loop checks the nullity of loc

Code:

for (prev=NULL; loc != NULL; loc = loc->next)

.. in this case, no... and then loc goes to the next element which is null...

Code:

for(..., loc = loc->next)

which is a problem because after that

Code:

prev = loc; // prev becomes null (but we don't want it to be)

remember in linked list, the last element isn't denoted by NULL... it's denoted by the last item BEFORE NULL
NULL is just like '\0' character in string.

got me? this is exactly what ss was saying

i don't see why you need the i in

Code:

for (i=0; loc != NULL; i++)

just do something like

Code:

for(loc = *start; loc != NULL; loc = loc -> next)

this, not only you make it easier to understand, but also make your code shorter because then you can take out the

Code:

 loc = *start

at the start of the else bit.

better yet

Code:

for(loc = *start; loc->next != NULL; loc = loc->next) { 
   // do nothing, it's all done in the loop
}

loc->next = temp;