You have a SINGLY linked list in memory of at least 1000 nodes (perhaps many more). I give you a pointer to ONE of the elements. (You don't know to which one.)

Upon examination, you discover that the pointer to the next node is not NULL (indicating that we're not at the last node in the list).

Your mission, should you decide to accept it, is to delete the current node, and maintain the valid linked list.

First, how do you go about doing that?

Second, how do you go about doing that in fixed space (i.e., you have only 64 bytes of memory as scratch space, so you can't replicate the rest of the linked list in memory, nor store more than 16 4-byte pointers)?

Node *temp = current->next;
current->val = current->next->val;
current->next = current->next->next;
free(temp->val);
free(temp);

Or something like that. Been a while for C.

The idea is that you move the next node's values into the current node, then have the current node point to the node following the next node, then you can delete the next node.

Posted by David Hanna on 2003-12-03 21:10:15