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Re: Can Java compute 9^(9^9) ?

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Maybe should raise an issue for OpenJDK.

Still researching, not yet sure what goes

wrong with Java BigInteger here...

Am Dienstag, 5. Juni 2018 16:17:21 UTC+2 schrieb burs...@gmail.com:
> There is something wrong with the 16 minutes.
> GNU bignums can do it in 8.5 secs:
> 
>    Welcome to SWI-Prolog (threaded, 64 bits, version 7.7.15)
>    SWI-Prolog comes with ABSOLUTELY NO WARRANTY. This is free software.
> 
>    ?- [user].
>    pow(_,0,1) :- !.
>    pow(X,1,X) :- !.
>    pow(X,N,Y) :-
>         M is N//2, pow(X,M,A),
>         J is N mod 2, pow(X,J,B),
>         Y is (A*A)*B. 
>    ^D
> 
>    ?- pow(9,9,X).
>    X = 387420489.
> 
>    ?- time((pow(9,9,X), pow(9,X,_))).
>    % 159 inferences, 7.500 CPU in 8.514 seconds (88% CPU, 21 Lips) 
> 
> I need to check again. Why it took 16 minutes...
> 
> Am Freitag, 1. Juni 2018 20:21:01 UTC+2 schrieb j4n bur53:
> > Came back from dinner:
> > 
> > ?- time((_ is 9^(9^9))).
> > % Up 974,318 ms, GC 9,302 ms, Thread Cpu 962,688 ms (Current 06/01/18 
> > 19:54:01)
> > Yes
> > 
> > ?- statistics.
> > Max Memory           7,635,730,432 Bytes
> > Used Memory           765,913,440 Bytes
> > Free Memory          2,891,739,304 Bytes
> > Uptime                 2,466,670 Millis
> > GC Time                    9,315 Millis
> > Thread Cpu Time          963,812 Millis
> > Current Time          06/01/18 20:18:37
> > 
> > Eric Sosman schrieb:
> > > On 6/1/2018 1:20 PM, bursejan@gmail.com wrote:
> > >>
> > >> Can I compute 9^(9^9) with Java BigIntegers?
> > > 
> > >      Sure, given enough memory.  The product will have about 1.3 billion
> > > bits, or 19.2 million 64-bit `long's.
> > > 
> > >      The computation might take a while, though.  Be patient.
> > >

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Can Java compute 9^(9^9) ? bursejan@gmail.com - 2018-06-01 10:20 -0700
  Re: Can Java compute 9^(9^9) ? Eric Sosman <esosman@comcast-dot-net.invalid> - 2018-06-01 13:36 -0400
    Re: Can Java compute 9^(9^9) ? j4n bur53 <janburse@fastmail.fm> - 2018-06-01 20:20 +0200
      Re: Can Java compute 9^(9^9) ? bursejan@gmail.com - 2018-06-05 07:17 -0700
        Re: Can Java compute 9^(9^9) ? bursejan@gmail.com - 2018-06-05 07:29 -0700
          Re: Can Java compute 9^(9^9) ? bursejan@gmail.com - 2018-06-05 07:48 -0700
          Re: Can Java compute 9^(9^9) ? Eric Sosman <esosman@comcast-dot-net.invalid> - 2018-06-05 10:57 -0400
            Re: Can Java compute 9^(9^9) ? bursejan@gmail.com - 2018-06-05 09:32 -0700
              Re: Can Java compute 9^(9^9) ? Eric Sosman <esosman@comcast-dot-net.invalid> - 2018-06-05 13:58 -0400
                Re: Can Java compute 9^(9^9) ? bursejan@gmail.com - 2018-06-05 11:10 -0700
                Re: Can Java compute 9^(9^9) ? bursejan@gmail.com - 2018-06-05 11:21 -0700
                Re: Can Java compute 9^(9^9) ? Andreas Leitgeb <avl@logic.at> - 2018-06-06 08:50 +0000
                Re: Can Java compute 9^(9^9) ? bursejan@gmail.com - 2018-06-06 01:58 -0700
                Re: Can Java compute 9^(9^9) ? bursejan@gmail.com - 2018-06-06 02:01 -0700
                Re: Can Java compute 9^(9^9) ? bursejan@gmail.com - 2018-06-06 10:34 -0700
  Re: Can Java compute 9^(9^9) ? j4n bur53 <janburse@fastmail.fm> - 2018-06-09 21:06 +0200
    Re: Can Java compute 9^(9^9) ? v_borchert@despammed.com (Volker Borchert) - 2018-06-09 23:29 +0000
      Re: Can Java compute 9^(9^9) ? Martin Gregorie <martin@mydomain.invalid> - 2018-06-10 09:13 +0000
        Re: Can Java compute 9^(9^9) ? bursejan@gmail.com - 2018-06-10 02:31 -0700
          Re: Can Java compute 9^(9^9) ? Arne Vajhøj <arne@vajhoej.dk> - 2018-06-10 18:28 -0400
            Re: Can Java compute 9^(9^9) ? bursejan@gmail.com - 2018-06-10 15:48 -0700
              Re: Can Java compute 9^(9^9) ? bursejan@gmail.com - 2018-06-10 15:52 -0700
                Re: Can Java compute 9^(9^9) ? bursejan@gmail.com - 2018-06-10 15:58 -0700
              Re: Can Java compute 9^(9^9) ? Arne Vajhøj <arne@vajhoej.dk> - 2018-06-10 21:17 -0400
                Re: Can Java compute 9^(9^9) ? bursejan@gmail.com - 2018-06-11 13:20 -0700
                Re: Can Java compute 9^(9^9) ? bursejan@gmail.com - 2018-06-14 13:37 -0700

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