Another perft(7) challenge

[sje]

Another perft(7) challenge: two positions taken from the unique(7) set:

Position number one: [d]

Position number two: [d]

What is the perft(7) of position #1?
What is the perft(7) of position #2?

[syzygy]

115009794943

[sje]

Another perft(7) challenge: five more positions taken from the unique(7) set:

Position #1: [d]

Position #2: [d]

Position #3: [d]

Position #4: [d]

Position #5: [d]

What is the perft(7) of position #1?
What is the perft(7) of position #2?
What is the perft(7) of position #3?
What is the perft(7) of position #4?
What is the perft(7) of position #5?

[zullil]

115009794943

Code: Select all

FEN string = rnb1kbnr/ppp1pppp/3p4/1q6/2BPP3/8/PPPQ1PPP/RNB1K1NR b KQkq - 
Depth = 7
Leaf nodes = 115009794943
Time taken = 1519544 ms

More than 115 billion nodes. Not fast, but it seems my code can count correctly.

[Ajedrecista]

Hello Steven:

All the seven perft(7) counts were computed by JetChess 1.0.0.0 (1 GB of hash). I know: hashed perft, collisions... Anyway:

Code: Select all

Position #1.1:
rnb1kbnr/ppp1pppp/3p4/1q6/2BPP3/8/PPPQ1PPP/RNB1K1NR b KQkq - 2 4

perft(7) = 115,009,794,943

--------------------------------------------------

Position #1.2:
rnb1kbnr/ppp1pppp/3p4/5q2/6Q1/4PNP1/PPPP1P1P/RNB1KB1R b KQkq - 0 4

perft(7) = 115,009,794,943

--------------------------------------------------

Position #2.1:
rnQ1kbnr/p1p1pppp/3p4/5b2/8/4P3/PPPP1PPP/RNB1KBNR b KQkq - 0 4

perft(7) = 342,652,817

--------------------------------------------------

Position #2.2:
rnQ1kbnr/p1p1pppp/3p4/8/6b1/4P3/PPPP1PPP/RNB1KBNR b KQkq - 0 4

perft(7) =342,652,817

--------------------------------------------------

Position #2.3:
rnQ1kbnr/p1p1pppp/3p4/8/8/4P2b/PPPP1PPP/RNB1KBNR b KQkq - 0 4

perft(7) = 342,652,817

--------------------------------------------------

Position #2.4:
rnQ1kbnr/p1p1pppp/3pb3/8/8/4P3/PPPP1PPP/RNB1KBNR b KQkq - 0 4

perft(7) = 342,652,817

--------------------------------------------------

Position #2.5:
rnQ1kbnr/p1pbpppp/3p4/8/8/4P3/PPPP1PPP/RNB1KBNR b KQkq - 0 4

perft(7) = 342,652,817

The results are not given in divided form just to not make this post very long.

The same values of [perft(7), position #2.i] are not a surprise because [perft(1), position #2.i] = 1; I have not checked it, but I am sure that [perft(j), position #2.i] is the same for every j and i = 1, ..., 5. After Bxc8 (only move), the resulting position is the same in the five cases.

But the finding of [perft(7), position #1.1] = [perft(7), position #1.2] is cool!

Regards from Spain.

Ajedrecista.

[Henk]

I'm too busy computing perft(15). So I have no time for this.

[sje]

[d]
[d]
I have more than 90,000 of these so far.

[syzygy]

115009794943

Code: Select all

FEN string = rnb1kbnr/ppp1pppp/3p4/1q6/2BPP3/8/PPPQ1PPP/RNB1K1NR b KQkq - 
Depth = 7
Leaf nodes = 115009794943
Time taken = 1519544 ms

More than 115 billion nodes. Not fast, but it seems my code can count correctly.

Code: Select all

rnb1kbnr/ppp1pppp/3p4/1q6/2BPP3/8/PPPQ1PPP/RNB1K1NR b KQkq -

   +---+---+---+---+---+---+---+---+
   | R*| N*| B*|   | K*| B*| N*| R*|
   +---+---+---+---+---+---+---+---+
   | P*| P*| P*|   | P*| P*| P*| P*|
   +---+---+---+---+---+---+---+---+
   |   |   |   | P*|   |   |   |   |
   +---+---+---+---+---+---+---+---+
   |   | Q*|   |   |   |   |   |   |
   +---+---+---+---+---+---+---+---+
   |   |   | B | P | P |   |   |   |
   +---+---+---+---+---+---+---+---+
   |   |   |   |   |   |   |   |   |
   +---+---+---+---+---+---+---+---+
   | P | P | P | Q |   | P | P | P |
   +---+---+---+---+---+---+---+---+
   | R | N | B |   | K |   | N | R |
   +---+---+---+---+---+---+---+---+

perft[ 1] =           42 (  0:00.000)
perft[ 2] =         1618 (  0:00.000)
perft[ 3] =        60768 (  0:00.000)
perft[ 4] =      2319228 (  0:00.003)
perft[ 5] =     84238361 (  0:00.115)
perft[ 6] =   3226540139 (  0:04.486)
perft[ 7] = 115009794943 (  2:36.726)