Created
October 3, 2012 00:35
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Stern-Brocot Pi
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#!/usr/bin/env ruby | |
require 'rational' | |
require 'bigdecimal' | |
PI = BigDecimal.new(" | |
3.141592653589793238462643383279502884197169399375105820974944592307816406286 | |
208998628034825342117067982148086513282306647093844609550582231725359408128481 | |
117450284102701938521105559644622948954930381964428810975665933446128475648233 | |
786783165271201909145648566923460348610454326648213393607260249141273724587006 | |
606315588174881520920962829254091715364367892590360011330530548820466521384146 | |
951941511609433057270365759591953092186117381932611793105118548074462379962749 | |
567351885752724891227938183011949129833673362440656643086021394946395224737190 | |
702179860943702770539217176293176752384674818467669405132000568127145263560827 | |
785771342757789609173637178721468440901224953430146549585371050792279689258923 | |
542019956112129021960864034418159813629774771309960518707211349999998372978049 | |
951059731732816096318595024459455346908302642522308253344685035261931188171010 | |
003137838752886587533208381420617177669147303598253490428755468731159562863882 | |
353787593751957781857780532171226806613001927876611195909216420198938095257201 | |
065485863278865936153381827968230301952035301852968995773622599413891249721775 | |
283479131515574857242454150695950829533116861727855889075098381754637464939319 | |
255060400927701671139009848824012858361603563707660104710181942955596198946767 | |
837449448255379774726847104047534646208046684259069491293313677028989152104752 | |
162056966024058038150193511253382430035587640247496473263914199272604269922796 | |
782354781636009341721641219924586315030286182974555706749838505494588586926995 | |
690927210797509302955321165344987202755960236480665499119881834797753566369807 | |
426542527862551818417574672890977772793800081647060016145249192173217214772350 | |
141441973568548161361157352552133475741849468438523323907394143334547762416862 | |
518983569485562099219222184272550254256887671790494601653466804988627232791786 | |
085784383827967976681454100953883786360950680064225125205117392984896084128488 | |
626945604241965285022210661186306744278622039194945047123713786960956364371917 | |
287467764657573962413890865832645995813390478027590099465764078951269468398352 | |
595709825822620522489407726719478268482601476990902640136394437455305068203496 | |
252451749399651431429809190659250937221696461515709858387410597885959772975498 | |
930161753928468138268683868942774155991855925245953959431049972524680845987273 | |
644695848653836736222626099124608051243884390451244136549762780797715691435997 | |
700129616089441694868555848406353422072225828488648158456028506016842739452267 | |
467678895252138522549954666727823986456596116354886230577456498035593634568174 | |
324112515076069479451096596094025228879710893145669136867228748940560101503308 | |
617928680920874760917824938589009714909675985261365549781893129784821682998948 | |
722658804857564014270477555132379641451523746234364542858444795265867821051141 | |
354735739523113427166102135969536231442952484937187110145765403590279934403742 | |
007310578539062198387447808478489683321445713868751943506430218453191048481005 | |
370614680674919278191197939952061419663428754440643745123718192179998391015919 | |
561814675142691239748940907186494231961567945208095146550225231603881930142093 | |
".strip.gsub("\n", '')) | |
print 'RR' | |
l = Rational(2, 1) | |
m = Rational(3, 1) | |
r = Rational(4, 1) | |
2000.times do | |
bm = BigDecimal.new(m.numerator.to_s) / BigDecimal.new(m.denominator.to_s) | |
if bm < PI # go right | |
print 'R' | |
l = m | |
m = Rational(r.numerator + m.numerator, r.denominator + m.denominator) | |
else # go left | |
print 'L' | |
r = m | |
m = Rational(l.numerator + m.numerator, l.denominator + m.denominator) | |
end | |
end | |
puts |
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