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For generating puzzles it's really useful since it lets you determine if a randomly generated puzzle has only one possible path to solving it (exact cover problem). And it's fast so adding it to a pipeline doesn't incur much if any overhead.


Is there any property in particular of dancing links that you think helps in determining this, or is it just that a backtracking search can be used to test all cases?

For pen-and-paper puzzles like Sudoku there is usually the goal that a solution should be findable by a series of deductive steps. For 9x9 Sudoku, most deductive steps used correspond to the effects well-known propagation techniques offer[1]. With a suitable propagation level, if the puzzle is solved search-free, then one knows that both there is only one solution and that there is a deductive path to solve it.

[1]: See "Sudoku as a Constraint Problem", Helmut Simonis, https://ai.dmi.unibas.ch/_files/teaching/fs21/ai/material/ai... for some data on 9x9 Sudoku difficulty and the propagation techniques that are needed for search-free solving.


Does that have blackouts for "local" teams? I'm 1-2 hours (traffic depending) from the Mets and MLB subscription in the past was useless for live games due to blackout restrictions.


No local blackouts for the new AppleTV MLS deal.


There is a whole world of employers who need tech folks who aren't google and friends.


That's just been the case for 2.1 and 3.1, future versions will jump a version each year (next is v5) with every other year being LTS. Of course, we'll see if it actually goes as planned. I don't think I've seen them change course from the announcement last year.

https://devblogs.microsoft.com/dotnet/introducing-net-5/


All Altra shoes are zero-drop, so heel and forefoot are at the same level. It doesn't mean there's no padding.


Visual Studio itself also does that (I forget when it was introduced; a few versions back I think?). I haven't used Resharper in a long time, so I'm not sure how it compares now, though.


I started seeing it on VS2017. I use it a lot in VS2019.


Is making your own an option in the UK? I have a few friends in the US that love it, but I think you need easy service for the canisters. More effort to be sure, but at least then you can use whatever syrup you like.


Since this comes up every year, might as well point out this isn't an isolated case.

Tweet thread covering various ones (as of last year): https://twitter.com/mikemayerMMO/status/1013295573779312640


Most deferred payments don't take a previously agreed upon amount and apply interest to them though. They're usually agreed upon at the beginning of the contract and allow the team to get a discount on the total dollar figure via the time value of money.


Remote work? I rarely have in-person client meetings anymore. And honestly at my old job it had offices around the country so even then there were people I'd worked on projects with for years and had never met in person.


Backtracking as a strategy definitely seems... underwhelming. But it does have its uses. I wrote a few solvers, and they all served a different purpose. One was based on Norvig's python post on the subject; I used that to generate many puzzles very quickly. Then I used a backtracker (using Knuth's Dancing Links) to reduce the set to puzzles with only a single solution. The last solver was a "human" solver that used various known strategies; this let me grade difficulty without having to manually attempt every puzzle (although I still found it useful in my app UI to tag puzzles as being too hard/easy). The human solver is incredibly inefficient, but the one with the most room for growth (new strats, etc).


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