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From: "Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org>
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Subject: Re: advent of code day 10
Date: Sat, 12 Dec 2020 23:25:41 +0100
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On 12/12/20 9:17 PM, Stephen Leake wrote:
> "gautier...@hotmail.com" <gautier_niouzes@hotmail.com> writes:
> 
>> On Friday, December 11, 2020 at 4:39:36 AM UTC+1, Stephen Leake wrote:
>>> the final total is larger than 64 bits
>> The total for your data is 3022415986688, it holds in 42 bits...
> 
> hmm. I got constraint error when I used Long_Integer; maybe that's not
> 64 bits? Using Ada.Big_Numbers.Big_Integers was a good exercise anyway.

That sounds like C thinking. If you need 64 bits, say so, don't hope that 
optional language-defined types will be big enough.

type S is range -(2 ** 63) + 1 .. 2 ** 63 - 1;
type U is mod 2 ** 64;

I used

type U is mod System.Max_Binary_Modulus;

-- 
Jeff Carter
"Frankie Wolf, wanted by Federal authorities for
dancing with a mailman."
Take the Money and Run
143