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Subject: Re: The "Strand" puzzle --- ( Continued Fractions using Lisp
 orPython? )
Date: Thu, 1 Aug 2024 21:50:51 +0200
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Am 01.08.2024 um 21:47 schrieb HenHanna:
> On 8/1/2024 2:33 AM, B. Pym wrote:
>> HenHanna wrote:
>>
>>>>> e.g. -------- For the (street)  Numbers (1,2,3,4,5,6,7,8)
>>>>>
>>>>>         (1,2,3,4,5)  and  (7,8)  both add up to 15.
>>>>>
>>>>>
>>>>>
>>>>> "In a given street of houses with consecutive numbers between
>>>>> 50 and 500, find the house number, for which, the sum of
>>>>> numbers on the left is equal to the sum of numbers on the
>>>>> right"
> 
>>
>> Gauche Scheme
>>
>> (define (strand lst)
>>    (let go ((left-sum 0) (tail lst))
>>      (if (null? tail)
>>        #f
>>        (let ((right-sum (fold + 0 (cdr tail))))
>>          (cond ((< left-sum right-sum)
>>                 (go (+ left-sum (car tail)) (cdr tail)))
>>                ((= left-sum right-sum) (car tail))
>>                (#t #f))))))
>>
>> (strand '(1 2 3 4 5 6 7 8))
>>    ===>
>> 6
>>
>> (lrange 2 5)
>>    ===>
>> (2 3 4)
>>
>> (any
>>    (lambda (n)
>>      (if (strand (lrange 50 n))
>>        n
>>        #f))
>>    (lrange 500 50 -1))
>>    ===>
>> 352
>>
>> (strand (lrange 50 352))
>>    ===>
>> 251
> 
> 
>                does your Newsreader  set  Followup-to automatically?
>                         pls  disable it.

https://vasya10.wordpress.com/2012/01/11/groovy-olc-2-strand-puzzle-1914/
> i still don't see how the prob is related to the Continued  Fraction.