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Re: Losing my mind: results change with/without printf() statements

From Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups comp.lang.c
Subject Re: Losing my mind: results change with/without printf() statements
Date 2021-07-13 22:58 +0100
Organization A noiseless patient Spider
Message-ID <87zgupub9o.fsf@bsb.me.uk> (permalink)
References (6 earlier) <c26b774a-e81f-47c4-9600-f6a41ce1333bn@googlegroups.com> <c48be299-dca3-4a90-9475-63adc97268fcn@googlegroups.com> <d6d4416e-bcac-4c16-b826-0f4fc812f555n@googlegroups.com> <87o8b7uvg4.fsf@bsb.me.uk> <10d61830-44df-4038-b7bb-a2ae3ecac3b4n@googlegroups.com>

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Michael S <already5chosen@yahoo.com> writes:

> On Monday, July 12, 2021 at 11:30:17 PM UTC+3, Ben Bacarisse wrote:
>> Michael S <already...@yahoo.com> writes: 
>> 
>> ...
>> > 30 9420183703185916092057240786 9433452244699134827931922856 
>> > 31 7955196982875614557 9433452252654331810807537413 
>> > 32 1044368729348834888241541279499 1053802181601489220052348816912 
>> > 
>> > Time: 172m45.059s 
>> > Peak working set size: 27,182,277,000 bytes 
>> > 
>> > The later number means that the same program when applied to 
>> > nDigits=33 will need approximately 110 GB of RAM. 
>> > Right now I have no access to computer that carries that much. 
>> > I do know how to make data structures approximately 1.7 times more 
>> > compact, but it will come at cost of rather significant 
>> > slowdown. Besides 110/1.7 = 64GB so it's borderline and most likely 
>> > wouldn't fit in physical memory anyway. 
>> > 
>> > So, the most reasonable thing to do would be to declare a victory and 
>> > stop right there.
>> This is very impressive. Barvo! 
>> 
>> I've not looked at your explanation just in case the mood takes me to 
>> have think about this myself, but I am curious abut one thing... Does 
>> your method bring the compute resources for the 1-10^19 case within the 
>> parameters we've been attributing to Project Euler problems -- about a 
>> minute on a moderate home computer? I think you did say, but I can't 
>> find it now. I'm just wondering if the problem setter had some other 
>> scheme in mind... 
>
> Yes, even the very first totally unoptimized (by later standards)
> variant calculates 1-1e19 in 6s consuming ~20MB of RAM.

Ah, right.  Thanks.  I think you did say that already.

-- 
Ben.

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Losing my mind: results change with/without printf() statements DFS <nospam@dfs.com> - 2021-06-30 12:26 -0400
  Re: Losing my mind: results change with/without printf() statements David Brown <david.brown@hesbynett.no> - 2021-06-30 19:03 +0200
    Re: Losing my mind: results change with/without printf() statements DFS <nospam@dfs.com> - 2021-06-30 13:58 -0400
      Re: Losing my mind: results change with/without printf() statements Bart <bc@freeuk.com> - 2021-06-30 19:44 +0100
        Re: Losing my mind: results change with/without printf() statements DFS <nospam@dfs.com> - 2021-06-30 16:16 -0400
          Re: Losing my mind: results change with/without printf() statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-07-01 00:03 +0100
            Re: Losing my mind: results change with/without printf() statements DFS <nospam@dfs.com> - 2021-06-30 23:54 -0400
              Re: Losing my mind: results change with/without printf() statements David Brown <david.brown@hesbynett.no> - 2021-07-01 10:56 +0200
              Re: Losing my mind: results change with/without printf() statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-07-01 10:38 +0100
                Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-02 02:49 -0700
                Re: Losing my mind: results change with/without printf() statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-07-02 14:44 +0100
                Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-02 07:48 -0700
                Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-02 09:25 -0700
                Re: Losing my mind: results change with/without printf() statements Bart <bc@freeuk.com> - 2021-07-02 18:33 +0100
                Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-04 01:27 -0700
                Re: Losing my mind: results change with/without printf() statements Bart <bc@freeuk.com> - 2021-07-04 15:19 +0100
                Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-04 09:04 -0700
                Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-04 09:51 -0700
          Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-02 03:20 -0700
            Re: Losing my mind: results change with/without printf() statements Bart <bc@freeuk.com> - 2021-07-02 11:42 +0100
              Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-02 04:47 -0700
          Re: Losing my mind: results change with/without printf() statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-07-02 15:21 +0100
            Re: Losing my mind: results change with/without printf() statements DFS <nospam@dfs.com> - 2021-07-02 11:37 -0400
            Re: Losing my mind: results change with/without printf() statements Bart <bc@freeuk.com> - 2021-07-02 17:06 +0100
            Re: Losing my mind: results change with/without printf() statements Kaz Kylheku <563-365-8930@kylheku.com> - 2021-07-02 17:41 +0000
              Re: Losing my mind: results change with/without printf() statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-07-02 19:09 +0100
                Re: Losing my mind: results change with/without printf() statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-07-02 19:48 +0100
                Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-04 03:21 -0700
                Re: Losing my mind: results change with/without printf() statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-07-04 14:01 +0100
                Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-05 02:44 -0700
                Re: Losing my mind: results change with/without printf() statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-07-05 14:43 +0100
                Re: Losing my mind: results change with/without printf() statements kegs@provalid.com (Kent Dickey) - 2021-07-05 19:42 -0500
                Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-06 03:36 -0700
                Re: Losing my mind: results change with/without printf() statements kegs@provalid.com (Kent Dickey) - 2021-07-06 12:27 -0500
                Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-06 16:02 -0700
                Re: Losing my mind: results change with/without printf() statements DFS <nospam@dfs.com> - 2021-07-06 20:30 -0400
                Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-08 01:02 -0700
                Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-09 05:52 -0700
                Re: Losing my mind: results change with/without printf() statements kegs@provalid.com (Kent Dickey) - 2021-07-09 08:24 -0500
                Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-09 07:20 -0700
                Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-10 15:27 -0700
                Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-12 00:56 -0700
                Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-12 12:01 -0700
                Re: Losing my mind: results change with/without printf() statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-07-12 21:30 +0100
                Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-13 00:33 -0700
                Re: Losing my mind: results change with/without printf() statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-07-13 22:58 +0100
                Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-20 13:38 -0700
                Re: Losing my mind: results change with/without printf() statements DFS <nospam@dfs.com> - 2021-07-09 11:23 -0400
                Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-09 08:43 -0700
                Re: Losing my mind: results change with/without printf() statements Mike Terry <news.dead.person.stones@darjeeling.plus.com> - 2021-07-11 16:40 +0100
                Re: Losing my mind: results change with/without printf() statements Michael S <already5chosen@yahoo.com> - 2021-07-12 02:51 -0700
                Re: Losing my mind: results change with/without printf() statements Mike Terry <news.dead.person.stones@darjeeling.plus.com> - 2021-07-12 16:57 +0100
                Re: Losing my mind: results change with/without printf() statements Mike Terry <news.dead.person.stones@darjeeling.plus.com> - 2021-07-12 17:25 +0100
                Re: Losing my mind: results change with/without printf() statements Mike Terry <news.dead.person.stones@darjeeling.plus.com> - 2021-07-20 18:03 +0100
      Re: Losing my mind: results change with/without printf() statements David Brown <david.brown@hesbynett.no> - 2021-07-01 10:46 +0200
        Re: Losing my mind: results change with/without printf() statements DFS <nospam@dfs.com> - 2021-07-02 11:52 -0400
          Re: Losing my mind: results change with/without printf() statements Bart <bc@freeuk.com> - 2021-07-02 17:16 +0100
            Re: Losing my mind: results change with/without printf() statements DFS <nospam@dfs.com> - 2021-07-02 13:27 -0400
      Re: Losing my mind: results change with/without printf() statements luser droog <luser.droog@gmail.com> - 2021-07-12 16:19 -0700
  Re: Losing my mind: results change with/without printf() statements Barry Schwarz <schwarzb@delq.com> - 2021-06-30 11:36 -0700
    Re: Losing my mind: results change with/without printf() statements DFS <nospam@dfs.com> - 2021-06-30 16:03 -0400
      Re: Losing my mind: results change with/without printf() statements Barry Schwarz <schwarzb@delq.com> - 2021-06-30 13:22 -0700
      Re: Losing my mind: results change with/without printf() statements David Brown <david.brown@hesbynett.no> - 2021-07-01 11:03 +0200
  Re: Losing my mind: results change with/without printf() statements Rosario19 <Ros@invalid.invalid> - 2021-07-01 10:49 +0200

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