我需要删除链表中的节点，如何找到它之前的节点，以便重新排列列表？

Question

It's for a school assignment. I have to use a search method that returns the node that I search for or the one right before it if it doesn't exist. Obviously if I want to delete a node it'll return that one node and I won't be able to find the one that comes before it. Here's the code for the search method:

private myNode search(myEntry searchEntry)
{
  myNode ref = first;
  myNode pre = null;

  while(ref != null)
  {
     if(searchEntry.compareTo(ref.data) < 0)
        break;
     pre = ref;
     ref = ref.link;
  }
  return pre;
}

first is the first node, ref is the pointer, pre is the node preceding the pointer. Maybe I'll use a doubly-linked list if it doesn't require me to rewrite things too much but if there's a simple way to find the predecessor of the node I'm trying to delete using this search method then I'd like to know. I'm not supposed to be using doubly-linked lists at all.

Answer 1

You can't do that with your search method. You have to implement a distinct search method that return the predecessor of the node and then delete it.

Answer 2

If you need to delete ref, than you return pre. To delete ref, you can write something like

pre = list.search(entry); //find the prescending node
ref = pre.link;           //get the node you want to delete
pre.link = ref.link;      //reassign link
ref.delete();             //delete node