rokicki

6 ms·

1.
by rokicki 25d ago
I've bounded God's number for this puzzle as between 87 (for which I have two explicit positions) and 108. I'm expecting to tighten those bounds. If I had to guess I'd put the number at 87 or 88.
2.
by rokicki 4mo ago
It's so odd that the only nontrivial example code in the paper is completely buggy. The find longest common prefix function of a list of strings fails (try ["a", "bc", "ade"]).
3.
by rokicki 10mo ago
For Cochlear brand your kit should include backup coils, and replacement is overnight. If you turn on lights (child mode) the processor lights indicate streaming with blue. I love my cochlear implants even though the integration UI and re
4.
by rokicki 11mo ago
It should take 105 repetitions: https://alpha.twizzle.net/explore/?alg=%28U+R%29105 Unless by "same direction" you mean "opposite direction", in which case 63 works: https://alpha.twizzle
5.
Finally: Performant parallel in-place sorting in C++(github.com)
3 points by rokicki 1y ago|0 comments
6.
by rokicki 2y ago
Nice blog post, but I really wish the author knew how to use apostrophes. (Or the difference between its and it's, if it's not the typographical character he doesn't like.) It's just so jarring to be reading along and
7.
by rokicki 2y ago
This expression is nonzero iff reverse(a) > reverse(b) (where reverse is the bitreversal of an unsigned number). It (using the address of the nodes as arguments) can serve as a tiebreaker in a Cartesian tree (such as one implementing a f
8.
by rokicki 2y ago
There's a nice elegant description of what it does, mathematically, and a significant use in Computer Science.
9.
by rokicki 2y ago
To take this to the next level: what does [(a^b) & (-(a^b)) & a] compute? (Assume unsigned arithmetic.) And then after that: what use can this be put to?
10.
by rokicki 2y ago
To solve a particular position, I just use level-by-level breadth-first search until a level contains two values that are reverses of each other. To explore the entire state space of possible initial positions, I use a number of tricks; I&#
11.
by rokicki 2y ago
Finished with a full-state search of 12; worst case is indeed 130. Found a game for n=14 that takes 172 moves: 6 11 8 2 7 10 9 12 4 1 14 3.
12.
by rokicki 2y ago
Finished with a full state-space search of 11; worst case is indeed 106 (vs 126 for 10).
13.
by rokicki 2y ago
Here are the maximum number of steps required through 10, and likely maximum number of steps required through 12: 6: 14 7: 26 8: 74 9: 86 10: 126 11: 106 (?) (full state space not explored) 12: 130 (?) (full state space not explored)