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Jun 30, 2014 at 12:45 vote accept R B
Jun 13, 2014 at 23:44 answer added Ari Trachtenberg timeline score: 0
Jun 13, 2014 at 20:26 comment added R B @AriTrachtenberg - you are correct that the problem didn't say anything about it, but I was wondering if it's possible. What is the possible runtime of adding/deleting items in your suggestion? Do you think it's possible to assign the enumeration encoding such that operations will be doable in $O(k)$ time? By the way, you can write your previous comment as an answer, and we can have this discussion in its comments.
Jun 13, 2014 at 20:14 comment added Ari Trachtenberg @R B - Insertion / deletion of set elements or into the universal set? The problem didn't say anything about the running time of insertions/deletions.
Jun 13, 2014 at 19:59 comment added R B @AriTrachtenberg - can you do that and support insertion/deletion/lookup in time depending only on $k$?
Jun 13, 2014 at 19:56 comment added Ari Trachtenberg You can implement the information-theoretic optimum by listing out (or computing) all ${n \choose k}$ possible subsets of length $k$ and giving each a binary encoding of $\log {n \choose k} \in O(k \log \frac{n}{k} )$ bits.
Jun 13, 2014 at 15:49 comment added R B @ZsbánAmbrus - I'm not sure I follow. Doesn't arithmetic coding encodes ordered words? How can I use it to encode an unordered set of letters without having to save the additional bits required for saving the order?
Jun 13, 2014 at 14:59 comment added Zsbán Ambrus Could you just use arithmetic coding?
Jun 13, 2014 at 13:23 history tweeted twitter.com/#!/StackCSTheory/status/477441191777017856
Jun 13, 2014 at 0:16 answer added jbapple timeline score: 5
Jun 12, 2014 at 22:44 history asked R B CC BY-SA 3.0