hadzilacos vassos - intro to theory of computation

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  • 8/3/2019 Hadzilacos Vassos - Intro to Theory of Computation

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    Kc|v{l gczl{ acv K[K F;1#6;1#6:0

    BGZVCJ\KZBCG ZCZDL ZDLCVR CA KCEP\ZHZBCG

    Qh{{c{ Dhjbihkc{

    Jlphvzelgz ca Kcep|zlv [kblgkl\gbqlv{bzr ca Zcvcgzc

    Zdl{l gczl{ hvl ibklg{lj |gjlv h Kvlhzbql Kceecg{ Hzzvbf|zbcg) Gcg%Kceelvkbhi) Gc Jlvbqh%zbql{ ibklg{l $KK FR%GK%GJ"' Rc| ehr kcpr) jb{zvbf|zl) hgj zvhg{ebz zdl{l gczl{ acv avll hgj}bzdc|z {llnbgm {plkbk plveb{{bcg avce zdl h|zdcv) h{ icgm h{ rc| hzzvbf|zl zdl }cvn zc bz{

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    cplj bg bz{ x|l{z acv bgql{zbmhzbgm vlhibzr' Hz v{z zdb{ hpplhv{ phvhjctbkhi? |gibnl zdl pdr{bkhihgj ibal {kblgkl{ zdl {|folkz ehzzlv ca ehzdlehzbk{ b{ gcz vlhibzr plv {l' Ehzdlehzbk{) cg bz{c}g) khggcz zlii |{ zdhz zdl eh{{ ca hg cfolkz bg eczbcg hfflkz{ zdl acvkl bz ltlvz{ cv zdhzzdl JGH b{ {zv|kz|vlj h{ h jc|fil dlibt) lqlg zdc|md ehzdlehzbk{ b{ kv|kbhi bg zdl pvlkb{ljl{kvbpzbcg ca fczd zdl{l ahkz{' Ehzdlehzbk{ jlhi{ }bzd hf{zvhkz kcg{zv|kzbcg{ ca zdl d|ehgebgj) {|kd h{ g|eflv{) {lz{) vlihzbcg{ hgj a|gkzbcg{'

    Z}c lilelgz{ ca ehzdlehzbk{ hvl zdl {c|vkl ca bz{ {|kkl{{ h{ h zcci acv zdl bgql{zbmhzbcgca vlhibzr? bz{ zlkdgbx|l{ hgj bz{ elzdcjcicmr' Hkkcvjbgmir) ehzdlehzbk{ b{ h zcci bg z}c

    bgzlvvlihzlj f|z jb{zbgkz }hr{' Abv{z) bz b{ h zcci bg zdl {zvhbmdzacv}hvj {lg{l bg }dbkd hdheelv b{ h zcci' ]l khg |{l ehzdlehzbk{ zc mlz h ocf jcgl? khik|ihzl zdl qci|el ca hkcepibkhzlj {dhpl) jlzlvebgl zdl zvholkzcvr ca hg cfolkz mbqlg zdl acvkl{ hkzbgm cg bz) lzk'Bg zdb{ vcil) ehzdlehzbk{ pvcqbjl{ |{ }bzd zlkdgbx|l{ acv plvacvebgm kcep|zhzbcghi zh{n{'[lkcgj) ehzdlehzbk{ b{ hi{c h zcci bg zdl il{{ zhgmbfil {lg{l bg }dbkd pihggbgm b{ h zcci' Bz b{dhvj zc pcbgz zc h {plkbk alhz|vl ca h dc|{l hzzvbf|zhfil zc zdl pihggbgm ca bz{ kcg{zv|kzbcg klvzhbgir dhvjlv zdhg pcbgzbgm zc h ghbi }dc{l pvl{lgkl b{ hzzvbf|zhfil zc zdl |{l ca zdldheelv f|z zdlvl b{ gc jc|fz zdhz }bzdc|z pihggbgm gc dc|{l }c|ij fl f|biz' Bg zdb{{|fzilv vcil) ehzdlehzbk{ pvcqbjl{ |{ gcz }bzd kcep|zhzbcghi zlkdgbx|l{ f|z }bzd h phvzbk|ihvelzdcjcicmr'

    Zdl elzdcjcicmr ca ehzdlehzbk{ dh{ ehgr h{plkz{> nlr hecgm zdle hvl?

    Hg ltpibkbz hgj |ghefbm|c|{ hkngc}iljmlelgz ca c|v h{{|epzbcg{' H {ehii {lz ca {bepil f|z pc}lva|i v|il{ ca zdc|mdz zdvc|md }dbkd }l khg vlhkd kcgki|%

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    Hg bgkibghzbcg zc hf{zvhkzbcg' Bg ehzdlehzbk{ }l bmgcvl zdl kcbgkbjlgzhi hgj ack|{ cg zdlmlvehgl' Zd|{) acv lthepil) bg ehzdlehzbk{ }l {z|jr g|eflv{ vlmhvjil{{ ca }dhz x|hgzbzr

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    Zdl z}c h{plkz{ ca zdl ehzdlehzbkhi lgzlvpvb{l ehzdlehzbk{ h{ h {lz ca kcep|zh%zbcghi zlkdgbx|l{ hgj ehzdlehzbk{ h{ h elzdcjcicmr ca pvlkb{l hgj lilmhgz vlh{cgbgm hvlgcz kc|gzlvpc{lj' Zdlr mc dhgj%bg%dhgj' Glbzdlv khg fl pvcplvir hppvlkbhzlj hgj eh{zlvlj}bzdc|z zdl czdlv' Bg er cpbgbcg zdlvl dh{ fllg h zvlgj bg zdl zlhkdbgm ca ehzdlehzbk{ $hzilh{z bg Gcvzd Helvbkh gcvzd ca zdl Vbc Mvhgjl" zc cqlvlepdh{b{l zdl acvelv hz zdl ltplg{l cazdl ihzzlv' Zdb{ lepdh{b{ b{ cazlg o|{zblj bg zdl ghel ca pvhkzbkhibzr cv vlilqhgkl' Bg erqbl} zdb{ kdcbkl) }lii%elhgbgm h{ bz ehr fl) b{ {lvbc|{ir eb{m|bjlj' Ilhvgbgm kcep|zhzbcghizlkdgbx|l{ b{) ca kc|v{l) glkl{{hvr gcz cgir flkh|{l ca zdlbv beeljbhzl hppibkhzbcg{ f|z hi{c

    flkh|{l }bzdc|z zdle zdlvl b{ gc ehzdlehzbk{' F|z B fliblql zdhz zdl hfbibzr acv pvlkb{l) vbm%cvc|{ hgj hf{zvhkz vlh{cgbgm b{ ecvl bepcvzhgz zdhg zdl eh{zlvr ca phvzbk|ihv kcep|zhzbcghizlkdgbx|l{' Bz b{ hi{c vlilqhgz zc h }bjlv {plkzv|e ca zh{n{ zdhg kcep|zhzbcghi zlkdgbx|l{ hvl'

    Zdl lepdh{b{ cg kcep|zhzbcghi zlkdgbx|l{ hz zdl ltplg{l ca ltpc{bgm {z|jlgz{ zc zdlelzdcjcicmr ca ehzdlehzbk{ b{ pvlqhilgz hz hii {zhml{ ca ehzdlehzbk{ lj|khzbcg) }bzd zdlltklpzbcg ca zdl }hr zdl {|folkz b{ zh|mdz zc ehzdlehzbk{ ehocv{ hz zdl |gbqlv{bzr ilqli' Acvvlh{cg{ B c|zibglj hfcql) B fliblql zdhz zdb{ b{ |gacvz|ghzl acv hii {z|jlgz{' Bz b{ phvzbk|ihvir|gacvz|ghzl acv kcep|zlv {kblgkl {z|jlgz{) zdl h|jblgkl acv }dbkd zdl{l gczl{ hvl bgzlgjlj)flkh|{l zdl elzdcjcicmr ca ehzdlehzbk{ b{ l{plkbhiir vlilqhgz zc kcep|zlv {kblgkl' Hf{zvhk%zbcg) pvlkb{l vlh{cgbgm) mlglvhibzr) lkblgkr? zdl{l hvl zdl zcci{ ca zdl zvhjl) hgj B ngc} ca gcflzzlv }hr ca {dhvplgbgm cgl{ eh{zlvr ca zdle zdhg zdvc|md zdl {z|jr ca ehzdlehzbk{'

    Bg zdl{l gczl{ B dhql zvblj zc pvl{lgz zdl {|folkz ehzzlv bg }dhz B fliblql b{ h fhihgklj}hr) phrbgm hzzlgzbcg gcz cgir zc zdl zlkdgbx|l{ zdhz {z|jlgz{ gllj zc eh{zlv f|z hi{c) hgjplvdhp{ ecvl bepcvzhgzir) zc ltpc{bgm zdle zc }dhz B dhql fllg khiibgm zdl elzdcjcicmr caehzdlehzbk{' Bz b{ er dcpl zdhz zdl gczl{ }bii dlip {z|jlgz{ mhbg hg |gjlv{zhgjbgm) hgj lqlgh }cvnbgm ngc}iljml) ca ehzdlehzbk{ h{ h zcci acv bgql{zbmhzbgm zdl zv|zd' Zc zdl ltzlgz zdlgczl{ hvl {|kkl{{a|i bg zdb{) B fliblql zdhz zdlr }bii hi{c {dlj {cel ibmdz zc zdl {lkcgj pcbgz caNlhz{ kc|pilz x|czlj hz zdl {zhvz ca zdl pvlahkl zdhz zv|zd b{ flh|zr'

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    Kcgzlgz{

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    8 Zdl |{l ca zc jlgczl zdl khvjbghibzbl{ cahii bggbzl {lz{ b{ hg cqlv{bepibkhzbcg' Hg bepcvzhgz phvz ca {lzzdlcvr b{ jlqczlj zc {z|jrbgm dc} zc kcephvl zdl khvjbghibzbl{ ca jbfflvlgz bggbzl {lz{' Vc|mdir {plhnbgm) z}c{lz{ H hgj F hvl {hbj zc dhql zdl {hel khvjbghibzr) ba }l khg {lz |p hg cgl%zc%cgl kcvvl{pcgjlgkl flz}llg

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    : KDHPZLV 0' PVLIBEBGHVBL[

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    0';' KHVZL[BHG PVCJ\KZ ba hz ilh{z cgl ca H hgj F b{ bggbzl hgj zdl czdlv b{ gcglepzr) zdlg H F b{ bggbzl' Hi{c)ba H) F hvl jb{zbgkz gcglepzr {lz{) H F 5 F H'

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    8';' KCEPILZL BGJ\KZBCG :8

    84 klgz{ |{bgm cgl :%klgz {zhep hgj z}c =%klgz {zhep{ $84 5 8 : . 6 ="> 82 klgz{ |{bgm zdvll :%klgz {zhep hgj cgl =%klgz {zhep{ $82 5 ; : . 8 ="> 60 klgz{ |{bgm ql :%klgz {zhep{ $60 5 < :"> 68 klgz{ |{bgm zdvll =%klgz {zhep{ $68 5 ; ="'

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    5 b

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    Bg zdl kh{l ca Kcgolkz|vl 8'8

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    :6 KDHPZLV 8' BGJ\KZBCG

    {|fzvll vcczlj hz cgl ca zdl kdbijvlg ca Z{ vccz' Acv lthepil) zdl zvll bg Abm|vl 8'8$f" dh{zdvll {|fzvll{? cgl kcgzhbg{ gcjl{ 6) < hgj 1> cgl kcgzhbg{ o|{z gcjl ;> hgj cgl kcgzhbg{ gcjl{:) =) 4 hgj 2'

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    8';' KCEPILZL BGJ\KZBCG :;

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    :: KDHPZLV 8' BGJ\KZBCG

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    :1 KDHPZLV 8' BGJ\KZBCG

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    8

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    Kdhpzlv 6

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    :4 KDHPZLV 6' KCVVLKZGL[[ CA BZLVHZBQL HGJ VLK\V[BQL PVCMVHE[

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    Zdl pc{zkcgjbzbcg vlehbg{ h{ bg Lthepil 6'8'H pvcmvhe zdhz {hzb{l{ zdb{ {plkbkhzbcg khg ltdbfbz hvfbzvhvr fldhqbc|v ba zdl mbqlg hvvhr

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    8Hg hvvhr b{ {cvzlj ba bz{ lilelgz{ hpplhv bg gcgjlkvlh{bgm cvjlv' Ecvl pvlkb{lir) H b{ {cvzlj ba) acv lhkd z{|kd zdhz 8 z 9 ilgmzd$H") H^zU H^z . 8U) }dlvl b{ h zczhi cvjlv ca zdl jhzh zrpl zc }dbkd zdl lilelgz{ca H flicgm' $]dlg }l {plhn ca h {cvzlj hvvhr }l hvl) bepibkbzir cv ltpibkbzir) h{{|ebgm h zczhi cvjlv ca zdljhzh zrpl{ zc }dbkd zdl hvvhr lilelgz{ flicgm' Acv lthepil) ba zdl hvvhr lilelgz{ kcgzhbg bgzlmlv{) zdl zczhicvjlv kc|ij fl zdl cv vlihzbcg cg bgzlmlv{> ba zdl hvvhr lilelgz{ kcgzhbg {zvbgm{) zdl zczhi cvjlv kc|ij fliltbkcmvhpdbk cvjlvbgm'" Gczl zdhz) bg mlglvhi) h {cvzlj hvvhr ehr kcgzhbg j|pibkhzl{'

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    6';' KCVVLKZGL[[ CA FBGHVR [LHVKD :2

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    czdlv}b{l bz vlz|vg{ 0'

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    6';' KCVVLKZGL[[ CA FBGHVR [LHVKD

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    6';' KCVVLKZGL[[ CA FBGHVR [LHVKD

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    6':' ZDL KCVVLKZGL[[ CA H E\IZBPIBKHZBCG PVCMVHE zc bgzlmlv%jbqbjl h g|eflv fr 80) }l jvcp zdl vbmdzec{z jbmbz'

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    10 KDHPZLV 6' KCVVLKZGL[[ CA BZLVHZBQL HGJ VLK\V[BQL PVCMVHE[

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    6'1' KCEELGZ[ CG PVCQBGM ZDL KCVVLKZGL[[ CA BZLVHZBQL PVCMVHE[18

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    16 KDHPZLV 6' KCVVLKZGL[[ CA BZLVHZBQL HGJ VLK\V[BQL PVCMVHE[

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    6'=' PVCCA CA KCVVLKZGL[[ CA VLK\V[BQL PVCMVHE[ 1;

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