Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
FM-index による全文検索
Search
Sponsored
·
Your Podcast. Everywhere. Effortlessly.
Share. Educate. Inspire. Entertain. You do you. We'll handle the rest.
→
Sho Iizuka
February 02, 2015
Programming
53
0
Share
FM-index による全文検索
https://kujira16.hateblo.jp/entry/2015/02/06/210630
Sho Iizuka
February 02, 2015
More Decks by Sho Iizuka
See All by Sho Iizuka
半年前の自分に教えたい systemd のハマりどころ
arosh
19
18k
Osaka.Stan#5 LT プログラミングコンテストのデータを分析した話
arosh
1
7.8k
簡潔データ構造輪講資料(順列)
arosh
1
9.2k
Pythonにおける日本語処理
arosh
1
2.2k
円と円の外接線の求め方
arosh
0
81
円と円の交点の求め方
arosh
0
47
Other Decks in Programming
See All in Programming
関係性から理解する"同一性"の型用語たち
pvcresin
2
620
代数的データ型って何が嬉しいの? #frontend_phpcon_do
kajitack
7
2.9k
AI開発を加速するためにテスト戦略を言語化した
yoshihiro_shu
0
110
Inside Stream API
skrb
1
490
プロパティの順序で型推論が壊れる!? TypeScript6.0の修正からContext-Sensitivityの仕組みを追う
bicstone
2
1.3k
初めてのRubyKaigiはこう見えた
jellyfish700
0
380
肥大化するレガシーコードに立ち向かうためのインターフェース分離と依存の逆転 / JJUG CCC 2026 Spring
hirokunimaeta
0
330
JavaDoc 再入門
nagise
0
230
TypeSpec で繋ぐ複数プロダクトの型安全
maroon8021
1
280
net-httpのHTTP/2対応について
naruse
0
400
柔軟なPDFレイアウトエディタを支える型システム設計 — Discriminated UnionとConditional Typeの実践
minako__ph
4
1.2k
Oxlintはいかにしてtsgolintのlint ruleを呼び出しているのか
syumai
2
1k
Featured
See All Featured
SEO in 2025: How to Prepare for the Future of Search
ipullrank
3
3.5k
Pawsitive SEO: Lessons from My Dog (and Many Mistakes) on Thriving as a Consultant in the Age of AI
davidcarrasco
0
150
Put a Button on it: Removing Barriers to Going Fast.
kastner
60
4.3k
Reflections from 52 weeks, 52 projects
jeffersonlam
356
21k
Templates, Plugins, & Blocks: Oh My! Creating the theme that thinks of everything
marktimemedia
31
2.8k
Build The Right Thing And Hit Your Dates
maggiecrowley
39
3.2k
Applied NLP in the Age of Generative AI
inesmontani
PRO
4
2.3k
Making Projects Easy
brettharned
120
6.7k
ReactJS: Keep Simple. Everything can be a component!
pedronauck
666
130k
New Earth Scene 8
popppiees
3
2.3k
SEO Brein meetup: CTRL+C is not how to scale international SEO
lindahogenes
1
2.7k
Leadership Guide Workshop - DevTernity 2021
reverentgeek
1
290
Transcript
FM-IndexʹΑΔશจݕࡧ ܭࢉػ࣮शE ࣗ༝՝
• จॻ͔ΒจࣈྻΛݕࡧ͢Δํ๏2௨ΓʹྨͰ͖Δ A. લॲཧ͕ෆཁͳํ๏ (ྗͤͳํ๏, KMP๏, BM๏) B. લॲཧ͕ඞཁͳํ๏ (సஔΠϯσοΫε,
ඌࣙྻ) • Bલॲཧͷ͕࣌ؒඞཁͳ͔ΘΓʹ, ಉ͡จॻ͔ΒԿճݕࡧ͢Δ߹AΑΓߴ • FM-IndexBʹྨ͞ΕΔํ๏Ͱ, จॻͷ͞ʹґଘ͠ͳ͍࣌ؒͰݕࡧͰ͖Δ
લॲཧ̍ɿඌࣙྻͷߏங จॻ mississippi mississippi$ ΤϯυϚʔΧ$ΛՃ mississippi$ ississippi$ ssissippi$ sissippi$ issippi$
ssippi$ sippi$ ippi$ ppi$ pi$ i$ $ ඌࣙͷྻڍ
લॲཧ̍ɿඌࣙྻͷߏங 0 mississippi$ 1 ississippi$ 2 ssissippi$ 3 sissippi$ 4
issippi$ 5 ssippi$ 6 sippi$ 7 ippi$ 8 ppi$ 9 pi$ 10 i$ 11 $ 11 $ 10 i$ 7 ippi$ 4 issippi$ 1 ississippi$ 0 mississippi$ 9 pi$ 8 ppi$ 6 sippi$ 3 sissippi$ 5 ssippi$ 2 ssissippi$ ࣙॻॱͰιʔτ͢Δ ※$ҙͷΞϧϑΝϕοτΑΓ ॱҐ͕খ͍͞ͱ͢Δ ඌࣙྻSA
લॲཧ̎ɿBWT (Burrows-Wheeler Transform) 11 $ 10 i$ 7 ippi$ 4
issippi$ 1 ississippi$ 0 mississippi$ 9 pi$ 8 ppi$ 6 sippi$ 3 sissippi$ 5 ssippi$ 2 ssissippi$ ݩͷจࣈྻʹ͓͚Δ ͻͱͭલͷจࣈʹ͢Δ i p s s m $ p i s s i i BWTจࣈྻT
ݕࡧॲཧ • BWTจࣈྻT = ipssm$pissii ʹ͍ͭͯ, ࣍ͷؔΛఆٛ͢Δ • Rank(c,p) :
T[0,p)ͷൣғͰ, ΞϧϑΝϕοτcͷग़ݱΛฦ͢ • RankLT(c) : TશମͰ, cΑΓॱҐ͕খ͍͞ ΞϧϑΝϕοτͷग़ݱΛฦ͢
ݕࡧॲཧ $ i$ ippi$ issippi$ ississippi$ mississippi$ pi$ ppi$ sippi$
sissippi$ ssippi$ ssissippi$ i p s s m $ p i s s i i BWTจࣈྻT ඌࣙྻSA
ݕࡧॲཧ $ i$ ippi$ issippi$ ississippi$ mississippi$ pi$ ppi$ sippi$
sissippi$ ssippi$ ssissippi$ i p s s m $ p i s s i i BWTจࣈྻT ඌࣙྻSA 'i'+"ppi$"ͷ ඌࣙྻ্Ͱͷ ग़ݱҐஔʁ
ݕࡧॲཧ $ i$ ippi$ issippi$ ississippi$ mississippi$ pi$ ppi$ sippi$
sissippi$ ssippi$ ssissippi$ i p s s m $ p i s s i i BWTจࣈྻT ඌࣙྻSA 'i'+"ppi$"ͷ ඌࣙྻ্Ͱͷ ग़ݱҐஔʁ
ݕࡧॲཧ $ i$ ippi$ issippi$ ississippi$ mississippi$ pi$ ppi$ sippi$
sissippi$ ssippi$ ssissippi$ i p s s m $ p i s s i i BWTจࣈྻT ඌࣙྻSA 'i'+"ppi$"ͷ ඌࣙྻ্Ͱͷ ग़ݱҐஔʁ LF-mapping c=T[p] ʹଓ͘จࣈྻͷ SA্Ͱͷग़ݱҐஔ RankLT(c)+Rank(c,p)
ݕࡧॲཧ $ i$ ippi$ issippi$ ississippi$ mississippi$ pi$ ppi$ sippi$
sissippi$ ssippi$ ssissippi$ i p s s m $ p i s s i i BWTจࣈྻT ඌࣙྻSA "ssi"ͷݕࡧ [RankLT('i')+Rank('i', 0), RankLT('i')+Rank('i', 12)) 'i'Ͱ࢝·Δ จࣈྻ
ݕࡧॲཧ $ i$ ippi$ issippi$ ississippi$ mississippi$ pi$ ppi$ sippi$
sissippi$ ssippi$ ssissippi$ i p s s m $ p i s s i i BWTจࣈྻT ඌࣙྻSA "ssi"ͷݕࡧ [RankLT('s')+Rank('s', 1), RankLT('s')+Rank('s', 5)) 's'+"i"Ͱ࢝·Δ จࣈྻ
ݕࡧॲཧ $ i$ ippi$ issippi$ ississippi$ mississippi$ pi$ ppi$ sippi$
sissippi$ ssippi$ ssissippi$ i p s s m $ p i s s i i BWTจࣈྻT ඌࣙྻSA "ssi"ͷݕࡧ [RankLT('s')+Rank('s', 8), RankLT('s')+Rank('s', 10)) 's'+"si"Ͱ࢝·Δ จࣈྻ
ݕࡧॲཧ • FM-index, ݕࡧจࣈྻʹରԠ͢ΔҐஔͷߜΓࠐΈΛ LF-mappingͷ܁Γฦ͠ʹΑͬͯߦ͏ • LF-mapping Rank ͱ RankLT
Ͱߦ͑Δ • ͜ͷ2ͭͷॲཧ, ΣʔϒϨοτΣʔϒϨοτߦྻΛ͑ O(log σ) ࣌ؒͰՄೳ (σ ΞϧϑΝϕοτͷछྨ) • LF-mappingΛݕࡧจࣈྻQͷ͚ͩ͞܁Γฦ͢ͷͰ, Ұճͷݕࡧ͕O(m log σ) ࣌ؒͰՄೳ (m Q ͷจࣈ) • ݕࡧ͕࣌ؒจॻͷ͞ʹґଘ͠ͳ͍
੍࡞ • ੨ۭจݿͰਓؾ͕͋Δਤॻ500Λରͱͨ͠ Σϒϒϥβ͔Β͑ΔΠϯΫϦϝϯλϧݕࡧΛ੍࡞ • ඌࣙྻͷߏஙsais.hxx (ߴͳϥΠϒϥϦ) Λ༻ • ΣʔϒϨοτߦྻͱFM-IndexࣗͰ࣮
(C++), boost-pythonʹΑΓPython༻ͷ֦ுϞδϡʔϧʹม • Flask (Web App Framework@Python) ͔Βݺͼग़͢
͏·͍͔͘ͳ͔ͬͨͱ͜Ζ • ͍͋·͍ݕࡧΛ࣮͠Α͏ͱͯ͠จݙΛ୳ͯ͠Έͨ → ฤूڑʹରͯ͠ࢦ͔͔࣌ؒΔΒ͍͠… • ࡞ͨ͠ࡧҾΛϑΝΠϧ͔ΒಡΈࠐΉॲཧͰ, طଘͷϥΠϒϥϦΛͬͨΒ༻ϝϞϦͷྔ͕രൃ (ݪҼෆ໌)
·ͱΊ • ߴͳจࣈྻݕࡧͷΞϧΰϦζϜΛ࣮ͯ͠Έͨ • ϒϥβ͔Β͑ΔΑ͏ʹͯ͠Έͨ ! • ࢀߟจݙ • Ԭݪ
େี. ߴจࣈྻղੳͷੈք. ؠॻళ. 2012.
(ิ) ΣʔϒϨοτ 3101212213 1000101101 10111 32223 10111 10001 ԼҐ2Ϗοτ →
ԼҐ1Ϗοτ → 0 1111 222 33 0 1 0 1 0 1