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Results tagged with open-problem
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user 664
Problems known to be open in the literature and any problem that, after being posed, is decided to be open by the community.
62
votes
How hard is unshuffling a string?
For the special case you mention when each character appears at most
four times, there is a simple reduction to 2-SAT (unless I'm missing
something...), as follows:
The crucial point is that for each …
- 1,399
12
votes
How hard is unshuffling a string?
Here is an algorithm that may have some chance of being correct though
it seems tricky to prove and I would not bet the house on it...
Let us say that $G$ is purged if for every edge $e$, there
exist …
- 1,399