3 ms·

Just curious, this wouldn't work for a circularly linked list in the case where there is only one element, right?

• tresta 15y ago
  Why wouldn't it? A xor A = 0. A xor 0 = A. That should work like a regular circularly linked list or am I missing something? edit Doh, now I understand. If this was allowed it wouldn't be possible to have a one-node non-circular list.
  • bbrtyth 15y ago
    It would be the reverse case if it were non-circular, returning 0.
  • ithkuil 15y ago
    You can encode "end of list" with another value like -1 which is usually safe since you can assume that addresses are at word aligned (so odd numbers cannot be addresses)
• pmjordan 15y ago
  Generally, it doesn't allow you to walk the list given the pointer to an entry. You always need to know the addresses of two adjacent list entries. And yes, this limits its usefulness in practice. I tend to only need doubly linked lists where I want to be able to remove or insert an arbitrary element without walking the list, and you can't do that with an xor list.