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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: project euler 26
Date: Mon, 4 Sep 2023 14:39:17 +0200
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On 2023-09-04 13:06, Niklas Holsti wrote:
> On 2023-09-04 12:19, CSYH (QAQ) wrote:
>> I am new to Ada, I know is there a good way to start this program?
>> thanks
>> https://projecteuler.net/problem=26
> 
> First invent/discover the method (algorithm) for solving the problem, 
> without thinking about the programming language.
> 
> I don't think any language has built-in features that would lead to a 
> direct solution, although some functional language with lazy evaluation 
> could come close, because such languages can manipulate unbounded 
> (potentially infinite) sequences of values. Such sequences can be 
> handled in Ada, too, but with more effort -- they are not "built in" to 
> Ada.

Infinite division does not require big numbers, which Ada 22 has, but I 
wound not use them anyway because the performance would be abysmal.

BTW, Ada is perfect for numeric algorithms no need to resort to 
functional mess... (:-))

The problem itself requires as you said mathematical analysis, because a 
naive method of comparing partial division result with itself is 
obviously wrong. E.g. let you have

    0.12341234...

you could not conclude that the period is (1234) because it could 
actually be (123412345).

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de