linked list

how can i delete a node in a single link list, if i know the address of that node(only) i.e to be deleted and i dont know the address of root node.

how can i find in a double linked list, if the pointer is missing.means, the pointer is not pointing to the next node and it may point to some other double linked list also.so i have to find out which node's pointer is missing

You can't. You need both addresses; the address of the node to delete, and the address of any of the preceding nodes. There's no other way, period.



Pointers are never "missing". They either contain an address, or they are NULL. That means, if you're looking at a pointer's value, you can't tell if which linked list it points to. To put it simple: the only thing you can determine from a pointer's value is if it's pointing somewhere, or not (NULL). It does not convey any type information at all.

Sorry

"how can i delete a node in a single link list, if i know the address of that node(only) i.e to be deleted and i dont know the address of root node."

- i was thinking of maybe a hack way to do it. if u can determine the size of the node, then u know how many bytes in memory it occupies. and i believe nodes in a list are all stored sequentially in memory, so u could offset the pointer to the node to get pointers to the nodes in front/back of it.

No. You're thinking of elements in an array. With linked lists the following scenario is possible:

• allocate memory for a node and add it to the list
• allocate more memory from the heap for other data structures
• allocate another node and add it to the list

In the above scenario, the chance of the two nodes being adjecent in memory is well-nigh nil.

Stupid question:
How could any functioning program find itself in the situation of not knowing the address of the root node of a linked list that it had created?

I don't understand how the situation ysd4477 is trying to solve could ever arise unless the program has a bug in it. In that case, the solution is to correct the code and recompile.

It's not a stupid question; it's a valid point



That's an example of ysd4477's description, and yes, it's either an implementation or design flaw.



Sounds like sound advice to me

yea i just figured out that wasnt possible... went to try it, and realized that you attach nodes on the fly

If the last item of your single linked list is not NULL (which is the standard way) but points to the first item of the linked list, there is a way in calculating the pointer to the item before the item to be deleted. Then you have a chance.