# Improving Fixnum#gcd(Fixnum)

**URL:** <https://www.ruby-forum.com/t/improving-fixnum-gcd-fixnum/132752>\
**Category:** Development\
**Created:** [March 24, 2008, 1:25pm UTC](https://www.ruby-forum.com/t/improving-fixnum-gcd-fixnum/132752 "2008-03-24T13:25:15Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Akinori\_MUSHA](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/b782af/32.png) [@Akinori\_MUSHA](https://www.ruby-forum.com/u/Akinori_MUSHA)\
**Post date:** [March 24, 2008, 1:25pm UTC](https://www.ruby-forum.com/t/improving-fixnum-gcd-fixnum/132752/1 "2008-03-24T13:25:15Z")

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　常に Integer#gcd(Integer) を使うのは遅いので Fixnum#gcd(Fixnum) を  
用意すれば Rational を始めとして性能が大幅改善するよ、とのこと。

[http://rubyforge.org/tracker/index.php?func=detail&aid=19034&group\_id=426&atid=1698](http://rubyforge.org/tracker/index.php?func=detail&aid=19034&group_id=426&atid=1698)

どうでしょうか。

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<div class="post-metadata">

**Author:** ![Akinori\_MUSHA](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/b782af/32.png) [@Akinori\_MUSHA](https://www.ruby-forum.com/u/Akinori_MUSHA)\
**Post date:** [March 24, 2008, 2:25pm UTC](https://www.ruby-forum.com/t/improving-fixnum-gcd-fixnum/132752/2 "2008-03-24T14:25:28Z")

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In message “Re: [ruby-dev:34116] Improving Fixnum#gcd(Fixnum)”  
on Mon, 24 Mar 2008 21:24:22 +0900, “Akinori MUSHA”  
[removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) writes:

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|  
|[http://rubyforge.org/tracker/index.php?func=detail&aid=19034&group\_id=426&atid=1698](http://rubyforge.org/tracker/index.php?func=detail&aid=19034&group_id=426&atid=1698)

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