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Created October 3, 2012 00:35
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Stern-Brocot Pi
#!/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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