Problem 918. Find the repeating decimal pattern!

Created by Matt Fig

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139 Solutions
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Last Solution submitted on Apr 15, 2022

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2 Comments

Andrew Newell on 20 Jun 2013

The tests are inconsistent with the statement of the problem. Finite strings like ..123451234512345 only repeat to the end of the string, then switch to zeros.

Rafael S.T. Vieira on 4 Oct 2020

The problem should specify the precision required, there are numbers that cannot be represented with doubles and are loosing significant digits. And this really becomes an issue when your test suite use less significant digits to identify repeating patterns such as in cases 7 and 10. I was able to overcome this issue by using 14 digits, but some people used 16 (If someone else is having problems that's the way to go). Moreover, Andrew is right, a number like 0.333333 is technically not a repeating decimal.

Solution Comments

Solution 264188

1 Comment

1 Comment

Andrew Newell on 20 Jun 2013

If the number is a true repeater, then multiplying it by 999... for some number of 9's will result in an integer. The difficulty lies in the rounding. I had to tune the tolerance to deal with cases like .123451234512345, which aren't truly repeating.

Solution 131896

1 Comment

1 Comment

Khaled Hamed on 28 Aug 2012

Some cleaning up!

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decimal repeating string manipulation

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Problem 918. Find the repeating decimal pattern!

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Problem 918. Find the repeating decimal pattern!

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