Problem 273. Recurring Cycle Length (Inspired by Project Euler Problem 26)

Created by @bmtran (Bryant Tran)

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Last Solution submitted on Aug 11, 2020

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@bmtran (Bryant Tran) on 23 Feb 2012

sorry everyone, there was an issue in my reference solution used to generate the test suite. I have corrected this now.

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Solution 339591

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J.R.! Menzinger on 25 Oct 2013

Java + Signal processing aproach.

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Venu Lolla on 9 Mar 2012

Ah feeling a little guilty :| ...

Solution 33957

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Igor on 8 Feb 2012

Unless my math (or counting) is wrong, the result of 1/17 by long division has a 16-digit (not 15) recurring cycle. I cannot find an error in my code or hand calculations. Any help?

Alfonso Nieto-Castanon on 10 Feb 2012

I believe you are right, the current test results seem to use something similar to the current leading method which disregards the effect of 0's so it typically underestimates the cycle length when d>10...
I believe in the test problems the cycle lengths of 17,19,197,1977,12345 should be 16,18,98,658,822 instead...

Igor on 10 Feb 2012

And those are precisely the numbers I am getting.

Alan Chalker on 12 Feb 2012

Wikipedia agrees with you: http://en.wikipedia.org/wiki/Repeating_decimal#Cyclic_numbers

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Problem 273. Recurring Cycle Length (Inspired by Project Euler Problem 26)

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Problem 273. Recurring Cycle Length (Inspired by Project Euler Problem 26)

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