Aart's Blog

I made some improvements to my distributed implementation for computing perft and divide numbers for 8x8 checkers , and now computed depth 26 from the initial position, shown below. As reported earlier, the numbers were computed on a cluster of machines, further optimized with a "hard collision"-free transposition table as well as bulk counting. The move generator does not eliminate duplicate captures (viz. the situation where a king can capture the same pieces in different directions; a situation that starts to occur at depth 12 and up). move              divide(26) ---------------------------- 12-16:    111362678435231752 11-16:    112590257768420515 11-15:    101352649993886926 10-15:    100552646996749293 10-14:     86312674861234785  9-14:    103811787278058952  9-13:    136189763354484914 ---------------------------- perft(26) 752172458688067137    

Continuing my quest for deeper and deeper perft numbers for 8x8 checkers , I now computed depth 25 with the same distributed implementation I used earlier for depths up to 24. Below you see the perft breakdown per move (called "divide") from the initial position for depths 23, 24 and 25 (my depth 23 and 24 numbers were recently kindly confirmed by Murray Cash at the World Draughts Forum ). move          divide(23)        divide(24)          divide(25) -------------------------------------------------------------- 12-16:  1123463594881857  5192042148594780   24019313789608561 11-16:  1131373985922218  5248615918291379   24153215782987793 11-15:   984253557821317  4602138522979438   21659601983574539 10-15:  1000606302770349  4643700995955222   21609957136212495 10-14:   856779998157523  3988937724259353   18496978526984076  9-14:  1003310451936358  4712325943133747   22101040287502927  9-13:  1337748969176591  6263620622082081   29027372375205409 --------------------------

I just released version 4.0.5 of Chess for Android, available through Google Play or as direct download . This release mainly extends localization to more languages, but it also provides a new feature: copying the engine analysis to the clipboard. The following languages are now supported: Afrikaans (af) Chinese (zh) Czech (cs) Dutch (nl) English (en) French (fr) German (de) Hebrew (iw) Hindi (hi)        [coming soon] Icelandic (is)   [coming soon] Italian (it) Polish (pl) Portuguese (pt-br) Russian (ru) Spanish (es) Swedish (sv) Turkish (tr) Many thanks to my translation team: Vinícius Angiolucci, Lucas Braesch, A.N. Bürümcekci, Panna Chowdhury, Anton Hansson, Arnar Mar Hrafnkelsson, Michal Kaczmarek, Dara Koper, Morgan Lombard, Krizia Lopez, Dennis Prochko, Martin Sedlák, Philip Stutz, Haran Talmon, Ted Wong, and last but certainly not least C.R. Zamana!

Version 4.0 of Chess for Android, available at either Google Play or as direct download , focuses on localization and internationalization. All user facing text (except the chess notation and engine messages) has been translated into the following languages. English (the default) Dutch (translated myself) German (many thanks to Philip Stutz) Hebrew (many thanks to Haran Talmon) Polish (many thanks to Michal Kaczmarek) Spanish (many thanks to Krizia Lopez) Swedish (many thanks to Anton Hansson) If you spot any mistakes, if you would like to see support for other languages or, even better, if you would like to help with further localization, please drop me a private note.

I had been working on some general utilities for the micro-KIM , and used some spare time during the long weekend to finish a scrolling putchar utility that can output letters and digits to the 7-segment display in a scrolling fashion (some letters needed more improvisation than others, but my daughter Karina helped me designing all the letters and converting them to hex). Here is a demo.