Sorry for bumping this old topic (I discovered it by chance) and for the very long output of this post.sje wrote:Perft 31: 8/k7/3p4/p2P1p2/P2P1P2/8/8/K7 w - - 0 1
Ka2 10371366973326742232771
Kb1 13252601250407797823413
Kb2 19366999975110719410642
Count: 42990968198845259466826
That's forty-two sextillion nine hundred ninety quintillion nine hundred sixty-eight quadrillion one hundred ninety-eight trillion eight hundred forty-five billion two hundred fifty-nine million four hundred sixty-six thousand eight hundred twenty-six. By contrast, 2^64-1 is less than a thousandth of this at 18446744073709551615 or eighteen quintillion four hundred forty-six quadrillion seven hundred forty-four trillion seventy-three billion seven hundred nine million five hundred fifty-one thousand six hundred fifteen.
The Lisp program in use stores a hash and a count for each unique depth-1 position, so more than four GB were needed to hold the data because of the length of the hash signatures. This was handled by using ccl64, the 64 bit version of Clozure Common Lisp.
Results by JetChess 1.0.0.0 (single core, w32) using 1024 MB of hash (running in an Intel Pentium D930 (2999 MHz)):
[d]8/k7/3p4/p2P1p2/P2P1P2/8/8/K7 w - - 0 1
Code: Select all
1 Ka1-b1 13379419933284543
2 Ka1-a2 10458620597023933
3 Ka1-b2 19513928050956822
Total: 43351968581265298
43,351,968,581,265,298 (move pathes after 23 half moves).
Time: 131 ms (0:00:00.131).Code: Select all
1 Ka1-b1 69372789029739057
2 Ka1-a2 54229670648519839
3 Ka1-b2 101180509873108717
Total: 224782969551367613
224,782,969,551,367,613 (move pathes after 24 half moves).
Time: 670 ms (0:00:00.670).Code: Select all
1 Ka1-b1 419736306837795168
2 Ka1-a2 327999083762531157
3 Ka1-b2 612315810248920416
Total: 1360051200849246741
1,360,051,200,849,246,741 (move pathes after 25 half moves).
Time: 1.132 s (0:00:01.132).Code: Select all
1 Ka1-b1 2184210511941397691
2 Ka1-a2 1706910857137266354
3 Ka1-b2 3186337832855957271
Total: 7077459201934621316
7,077,459,201,934,621,316 (move pathes after 26 half moves).
Time: 2.699 s (0:00:02.699).Code: Select all
1 Ka1-b1 -5227128206127687200
2 Ka1-a2 -8115750359012173861
3 Ka1-b2 844241536037317366
Total: 5948107044607007921
5,948,107,044,607,007,921 (move pathes after 27 half moves).
Time: 4.864 s (0:00:04.864).Code: Select all
1 Ka1-b1 -4770507526121808229
2 Ka1-a2 -1401235102567543256
3 Ka1-b2 8478473141219228117
Total: 2306730512529876632
2,306,730,512,529,876,632 (move pathes after 28 half moves).
Time: 12.536 s (0:00:12.536).Code: Select all
1 Ka1-b1 -6447697976467554752
2 Ka1-a2 -5371963933529090433
3 Ka1-b2 1282029907223704729
Total: 7909112070936611160
7,909,112,070,936,611,160 (move pathes after 29 half moves).
Time: 23.006 s (0:00:23.006).Code: Select all
1 Ka1-b1 -6957651037998863439
2 Ka1-a2 -4638806270450955975
3 Ka1-b2 3350697430572130456
Total: -8245759877877688958
-8,245,759,877,877,688,958 (move pathes after 30 half moves).
Time: 61.990 s (0:01:01.990).Code: Select all
1 Ka1-b1 7839005484339763125
2 Ka1-a2 4296803901974224579
3 Ka1-b2 -2081302284309786158
Total: -8392236971705350070
-8,392,236,971,705,350,070 (move pathes after 31 half moves).
Time: 124.922 s (0:02:04.922).Code: Select all
1 Ka1-b1 -9173148514598047596
2 Ka1-a2 3725130762321234904
3 Ka1-b2 -637322109603466764
Total: -6085339861880279456
-6,085,339,861,880,279,456 (move pathes after 32 half moves).
Time: 410.541 s (0:06:50.541).Going with unique positions (running JetChess 1.0.0.0 again, but now with hash = 512 MB and 2 steps):
Code: Select all
Count 0: 124805
Count 1: 124743
Positions: 249548
249,548 (positions after 23 half moves).
Time: 817 ms (0:00:00.817).Code: Select all
Count 0: 196788
Count 1: 196770
Positions: 393558
393,558 (positions after 24 half moves).
Time: 1.500 s (0:00:01.500).Code: Select all
Count 0: 679752
Count 1: 681431
Positions: 1361183
1,361,183 (positions after 25 half moves).
Time: 6.603 s (0:00:06.603).Code: Select all
Count 0: 995228
Count 1: 995500
Positions: 1990728
1,990,728 (positions after 26 half moves).
Time: 9.968 s (0:00:09.968).Code: Select all
Count 0: 2944387
Count 1: 2944187
Positions: 5888574
5,888,574 (positions after 27 half moves).
Time: 29.396 s (0:00:29.396).Code: Select all
Count 0: 2048745
Count 1: 2049615
Count 2: 2047721
Count 3: 2051948
Positions: 8198029
8,198,029 (positions after 28 half moves).
Time: 109.065 s (0:01:49.065).Code: Select all
Count 0: 5287579
Count 1: 5285389
Count 2: 5286781
Count 3: 5284510
Positions: 21144259
21,144,259 (positions after 29 half moves).
Time: 286.295 s (0:04:46.295).Code: Select all
Count 0: 4218297
Count 1: 4220105
Count 2: 4219557
Count 3: 4219810
Count 4: 4219399
Count 5: 4219520
Count 6: 4219170
Count 7: 4219863
Positions: 33755721
33,755,721 (positions after 30 half moves).
Time: 4831.371 s (1:20:31.371).Regards from Spain.
Ajedrecista.
