LL(k) – A?aiiaoeee.
Ii?aaeaeaiea LL(k)-a?aiiaoee.
Aeey ia/aea i?aaeiieiaeei, /oi G=(N,E,P,S) – iaeiicia/iay a?aiiaoeea e
w=a1,a2…an – oeaii/ea ec L(G). Oiaaea nouanoaoao aaeeinoaaiiay
iineaaeiaaoaeueiinoue eaaiauaiaeeiuo oeaii/ae b0,b1..bm, aeey eioi?ie
S=b0,bi,pi TH bi+1 i?e 0), anee A®a` – aaeeinoaaiiia i?aaeei ec P, aeey
eioi?iai FIRSTk(a`) Ak L niaea?aeeo u;
ia ii?aaeaeaii, anee a iiiaeanoaa iaeaeoony aeaa e aieaa i?aaeea (yoo
neooaoeeth iacuaatho eiioeeeoii iaaeaeo i?aaeeaie)
Ia ii?iaeueiii ycuea yoi icia/aao /oi au?aaaouaaaony cia/aiea ioeaea,
anee u aiiaua ia yaeyaony oeaii/eie a?aiiaoeee, aica?auaaony i?aaeei
anee iii nouanoaoao e oieueei iaeii e anee ianeieueei i?aaee – oi
cia/aiea ia ii?aaeaeyaony.
AEA 2: Iino?iaiea LL(k)-oaaeeoe.
Aoiae: LL(k)- a?aiiaoeea G=(N,E,P,S).
Auoiae: Iiiaeanoai TG LL(k)-oaaeeoe, iaiaoiaeeiuo aeey iino?iaiey
oi?aaeythuae oaaeeoeu aeey G.
Iaoiae:
Iino?ieoue LL(k)-oaaeeoeo T0, niioaaonoaothuoth S e {e}.
Iieiaeeoue aia/aea TG={T0}.
Aeey eaaeaeie LL(k)-oaaeeoeu TITG, niaea?aeauae yeaiaio
T(u)=(A®x0B1x1…Bmxm,
aeey 1FiFm, anee T aua ia aoiaeeo a TG.
Iiaoi?youe oaa 3 iiea a TG iiaeii aeeth/aoue iiaua oaaeeoeu.
I?I: Iino?iei niioaaonoaothuaa iiiaeanoai LL(2)-oaaeeoe aeey a?aiiaoeee
S®aAaa|bAba e A ® b|e. Ia/iai n TG={TS,{e}} . Oae eae TS,{e}(aa)=(
S®aAaa,{aa}), oi a TG iaaei aeeth/eoue TA,{aa}. Aiaeiae/ii, oae eae
T0(bb)=( S®bAba,{ba}), oi a TG ioaeii oae aea aeeth/eoue . (Yeaiaiou
LL(2)-oaaeeoe TA,{aa} e TA,{ba}, ioee/iua io cia/aiey ioeaea, i?eaaaeaiu
a oaaeeoea ieaea). Nae/an TG={TS,{e},TA,{aa},TA,{ba}}, e aeai?eoi oaea
ia iiaeao aeeth/eoue a TG iiauo oaaeeoe, oae /oi yoi o?e LL(2)-oaaeeoeu
ia?acotho iiiaeanoai niioaaonoaothuaa a?aiiaoeea.
TA,{aa} TA,{ba}
u i?aaeei iiiaeanoaa u i?aaeei iiiaeanoaa
ba A ® b – ba A ® e –
aa A ® e – aa A ® b –
Oaia?ue aeaaeei aeai?eoi, eioi?ui iiaeii iino?ieoue ei??aeoioth
oi?aaeythuoth oaaeeoeo ii niioaaonoaothuaio iiiaeanoao LL(k)-oaaeeoe.
Oi?aaeyaiue yoie oaaeeoeae k-i?aaeneacuaathuee aeai?eoi aoaeao a
ea/anoaa iaaaceiiuo neiaieia oiio?aaeyoue aianoi iaoa?ieiaeia
LL(k)-oaaeeoeu.
AEA 3: Iino?iaiea oi?aaeythuae oaaeeoeu aeey LL(k)-a?aiiaoeee.
Aoiae : LL(k)-a?aiiaoeea e niioaaonoaothuaa iiiaeanoai TG LL(k)-oaaeeoe.
Auoiae : Ei??aeoiay oi?aaeythuay oaaeeoea M aeey G.
Iaoiae: M ii?aaeaeyaony ia iiiaeanoaa (TGEEE{$})?E*k neaaeothuei
ia?acii:
Anee A®x0B1x1…Bmxm – i?aaeei ec P n iiia?ii i e TA,LITG, oi aeey anao
u, aeey eioi?uo TA,L(u)=(A®x0B1x1…Bmxm,
M[TA,L,u]=(x0TB1,Y1…TBm,Ymxm,i).
M[a,av]=aua?in aeey anao vIE*(k-1).
M[$,e]=aeiione.
A inoaeueiuo neo/ayo M[X,u]=ioeaea
TS,{e} – ia/aeueiay oaaeeoea.
I?I: Iino?iei oi?aaeythuoth oaaeeoeo aeey LL(2)- a?aiiaoeee
S®aAaa
S®bAba
A®b
A®e
eniieuecoy niioaaonoaothuaa ae iiiaeanoai LL(2)-oaaeeoe, iaeaeaiiia a
i?aaeuaeouai i?eia?a. Aeai?eoi aeieaeai auaeaoue oaaeeoeo:
aa ab a ba bb b e
T0 aT1aa,1 aT1aa,1 bT2ba,2
T1 e,4 b,3
T2 e,4 b,3
a aua?in aua?in aua?in
b aua?in aua?in aua?in
$ aeiione*
aaea T0=TS,{e}, T1=TA,{aa} e T2=TA,{ba}. Iiae?acoiaaaaony, /oi a ionouo
y/aeeao – ioeaea. Aeiione* iaoiaeeony a iineaaeiae eieiiea. Aeey
aoiaeiie oeaii/ee bba 2-i?aaeneacuaathuee aeai?eoi auaeano oaeoth
iineaaeiaaoaeueiinoue oaeoia:
(bba,T0$,e) |- (bba,bT2ba$,2)
|- (ba,T2ba$,2)
|- (ba,ba$,24)
|- (a,a$,24)
|- (e,$,24)
O?I: Iienaiiue aeai?eoi no?ieo aeey LL(k)- a?aiiaoeee G=(N,E,P,S)
ei??aeoioth oaaeeoeo, oi?aaeythuoth ?aaioie niioaaonoaothuaai k-
i?aaeneacuaathuaai aeai?eoia.
I?I: ?anniio?ei LL(2)- a?aiiaoeeo G n i?aaeeaie:
S®e
S®abA
A®Saa
A®b
Iino?iei niioaaonoaothuea LL(2)-oaaeeoeu. Ia/iai n T0=TS,{e}. Caoai ii
T0 iaeaeai T1=TA,{e}, aeaeaa T2=TS,{aa} e T3=TA,{aa}:
T0 T2
u i?aaeei iiiaeanoaa u i?aaeei iiiaeanoaa
e S ®e – aa S ®e –
ab S ®abA {e} ab S ®abA {aa}
T1 T3
u i?aaeei iiiaeanoaa u i?aaeei iiiaeanoaa
b A ®b – aa A ®Saa {aa}
aa A ®Saa {aa} ab A ®Saa {aa}
ab A ®Saa {aa} ba A ®b –
Ii yoei oaaeeoeai iino?iei oi?aaeythuoth oaaeeoeo:
aa ab a ba bb b e
T0 abT1,2 e,1
T1 T2aa,3 T2aa,3 b,4
T2 e,1 abT3,2
T3 T2aa,3 T2aa,3 b,4
a aua?in aua?in aua?in
b aua?in aua?in aua?in
$ aeiione
Aeai?eoi iino?iaiiue ii oaaeeoea ?acaa?ao oeaii/eo abaa neaaeothuei
ia?acii:
(abaa,T0$,e) |- (abaa,abT1$,2)
|- (baa,bT1$,2)
|- (aa,T1$,2)
|- (aa,T2aa$,23)
|- (aa,aa$,231)
|- (a,a$,231)
|- (e,$,231)
O?I: *enei oaaia, auiieiyaiuo k- i?aaeneacuaathuei aeai?eoiii n
oi?aaeythuae oaaeeoeae, iino?iaiiie i?aaeuaeouei aeai?eoiii ii LL(k)-
a?aiiaoeea G, eeiaeii caaeneo io n, aaea n – aeeeiia aoiaeiie oeaii/ee.
I?iaa?ea LL(k)- oneiaey.
Ii ioiioaieth e i?iecaieueiie aeaiiie a?aiiaoeea G aicieeaao ?yae
anoanoaaiiuo aii?inia:
ssaeyaony ee G LL(k)-a?aiiaoeeie aeey aeaiiiai k ?
Nouanoaoao ee oaeia k, /oi G – LL(k)- a?aiiaoeea?
Oae eae aeey LL(1) eaaua ?acai?u no?iyony iniaaiii i?inoi, oi anee G ia
LL(1)- a?aiiaoeea, oi nouanoaoao ee yeaeaaeaioiay ae LL(1)- a?aiiaoeea
G’, aeey eioi?ie L(G) = L(G’)?
E niaeaeaieth, oieueei aeey ia?aiai aii?ina anoue ioaa/athuee ia iaai
aeai?eoi. Iiaeii iieacaoue, /oi aoi?ay e o?aouey i?iaeaiu aeai?eoie/anee
ia ?ac?aoeiu, ii yoi aeieacaoaeuenoai ia i?eaiaeeony. I?eaaaeai aeai?eoi
i?iaa?ee LL(k)- oneiaey:
AEA 4: I?iaa?ea LL(k)- oneiaey.
Aoiae: EN- a?aiiaoeea G=(N,E,P,S) e oeaeia /enei k.
Auoiae: «Aea» – anee G – LL(k)- a?aiiaoeea e «Iao» a i?ioeaiii neo/aa.
Iaoiae:
Nooue aeai?eoia naiaeeony e neaaeothuaio: Aeey eaaeaeiai iaoa?ieiaea,
eiathuaai aeaa eee aieaa i?aaeea ?ane?ooee au/eneyaony ia?ana/aiea
ia?auo k- neiaieia anao aiciiaeiuo oeaii/ae ?ane?ooee. Anee yoi
iiiaeanoai ionoi, oi ia?aoiaeyo e neaaeothuaio oa?ieiaeo, eia/a
caeai/eaatho ni cia/aieai «Iao». Anee ana ia?ana/aiey ionou –
caeai/eaatho ni cia/aieai «Aea». Aeey iieo/aiey ia?ana/aiey aeaoo i?aaee
iiaeii ainiieueciaaoueny caienueth: (FIRSTk(b`) AkL)C(FIRSTk(c`) AkL),
aaea L=FIRSTk(a`) e a` – oeaii/ea neiaieia iinea oa?ieiaea.
PAGE
PAGE 5
LL(k)-a?aiiaoeee
PAGE
PAGE \# “‘No?: ‘#’
Нашли опечатку? Выделите и нажмите CTRL+Enter
