0b68f84e44ae

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/data/2020/13.txt	Wed Dec 08 18:00:32 2021 -0800
@@ -0,0 +1,2 @@
+1000001
+29,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,41,x,x,x,x,x,x,x,x,x,577,x,x,x,x,x,x,x,x,x,x,x,x,13,17,x,x,x,x,19,x,x,x,23,x,x,x,x,x,x,x,601,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,37

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/data/2021/08.txt	Wed Dec 08 18:00:32 2021 -0800
@@ -0,0 +1,200 @@
+dfgabce cadfgb cefa ca aecbg dfcegb geabd ecbfg cab agcfbe | egbfadc dbgae gcfeb abgdfc
+fbcag eg dbge gcbfe acdgfe gec fdcegba efbdc fbedgc efabdc | ge fagbc dfebc eg
+da gdbcea gdcfbe acgbd dbfcgea ebad aecdfg afcbg adc ecdbg | afcegd dacebg ad cdbafeg
+gafeb ag acfbed ega ebadfg bfcge dgfa begcda edfba cfgedba | ag dafg dfcbgea feacdb
+cefdag gcea fag defca gbdaef afcdg dcbgf ga adfecbg fcbdea | geac cfedba cgea fadecg
+fcgaed abdecgf cfaed ceb febacd dbecf bc cbfa gecbad fbdeg | facde cfgade acdefb cbe
+bcgae cfedba efcbadg dafbc dfbe fcgbad ef aefgcd acfbe fea | abfcd cafbd fbde dcgbaf
+geabdc fedga cafdbg cd aefcbg adcge dac bdegafc cegab dceb | dcfgba cad cad deabcg
+gdecab fde aecf adbgfe egdcaf dgaebcf decfg bcfdg ef ceadg | cefdabg fcea efac edf
+cbgaf edfa bfgecd fcdbae debca dfb bcdaf bdcaeg fecgadb fd | cafdgeb gabcf df afdebc
+fdebgc egdfb bfcdg cfedgab fdeagb egcb fcb cfdeba cb fagcd | gebfd afdbgec bc gdcafbe
+cb gcdefa cdb bacg eabfd ebdac gdabec gcbefd bgdecaf caedg | cgdeab ebfdgca edgbca cbefadg
+efbc aecgbd ebgdfa ecbag afb cfgeadb bf cadgf bgfca egcabf | bf agdbce fab bfcdeag
+cedafg aecdbg fcd cgeda cdfag efcg agfdb defcab fagcebd cf | adgcfe daecg abcged fgedbca
+bcgaed cfdgea caebd gdebc bega fbecadg ge fcdaeb gde gfbdc | gabe eg cadebf ecgadf
+aefc abefg acfbge agedbf dbgce cab abgdfc ecbga ac bfdceag | beafgd ca ac ac
+afbde fedag becda dacegf baf gacdbfe fcabdg fgeb fgdabe fb | fb afbdge bcdea fedacbg
+bfd cdgbfa dgefca fabdeg cgebdfa cabd gfcda cbgef db dgfcb | bd badegcf acdb adegcf
+ef cfbgd cdbfe bef ceadb bfcgead aedf edbagc abgcef aecbdf | bcfegad bef bef fe
+cbagef beadgc fae deacb fcagd cgdebfa dfeb bdecaf fe fcdae | dfaceb efdb beafcg bdef
+gdfeacb bca gfeacb gfeca egcb bc dgeacf fabgd fbcdae gcbfa | bfdeca bca adbgf abdgf
+faedbc egcaf bdgaf agdebcf fagcb cab bcdgaf dbgc fbgead cb | bdgafc cb dgbfa bgcd
+dfabc bgacde ad dab edfa bdfec dbgefca facgb eacfbd fcgdeb | ecdbfag bedfc ebfcad bfcdge
+dfegbc cfagb ba gefbc abec bfcdega bfa egadbf fgbcea fgcda | eafbdg ebfgc fgbdcea ba
+fgdebca dgbcea adbce cfaedb acebf ef efc cfabg edgafc fedb | fdeb fce gcfab bafgc
+cfdg daefgcb caedgb aefbc cbdag fg fdbgac fbg beagdf fbcga | dgfc fecgabd fgcd gbf
+cbadef abgdef cfea ac gedbc dcbafg dca fdbecag dceab deafb | eafc ebfdga cefa abcde
+fcbged ebdca bde ceagb abcdfeg bd cdaef cgabed ecgfab bgda | baecd dgbcea ecafd dbag
+bfeag cdabf dbeacg dgbcefa eda fdabge bafde ed egfd ebcafg | ebfcadg defg fadbe cfbgea
+bfd dgbec gfcadb ecdf aefbg cfbgead fd gcbdfe debgf gcdeab | ecdbga aebgf abcfgde fd
+ecgfda bcafe dgbefca dagcb dfc acdfb cdabfe cebfag fbde fd | bgdefac cfd febgac df
+dcafb dgafcb dbeacf bdga degbcfa cgbaf ga fga efdgca cegfb | ag beagdfc abcfg gcdeaf
+cgbfd fegcba ecgfb cbe dafebg bdface gace ec fcgdeab eagfb | gcdfb acge ecb cebgf
+adbcgf ef fged feb dabfgce bdgfc becfgd dcabe febgac bdfec | cgdbf fdcgeb afcbge fbdgc
+cg dagfc dfagbc cgab dagbf gbdcfe dgc aefgdbc aecdf bafegd | cg gfacbed bfgad bgacfed
+cadfeg cfdegba edagcb fae faebc decfb fa aebcg fgba egafcb | baegc fa acfbe af
+fed bcdge fcbae gbfd gfabecd cdaegb df egdfac egcfbd becdf | cadegf edcgbf fcbde dbgf
+fadcg beafcd cedbag edabg abdfge bdagf fba dgcbaef fb fbge | deafcgb dfcaeb geadfb ecfgdba
+bec fbcea cgbf bfgcea cdefa cgadeb cb fdbeag bdaegcf fgabe | ebfacg bgcf cb bc
+gb agdbce efacgd cgdfbe agdec afcdb ebag gcb eadfgcb bdgac | efcbagd bedcag bgc baeg
+fbe dcbgae cedgfba bcgefa bfdge bf dafge edbgc fcdb bcfdeg | bdfc fdabgce ebgfd fegbd
+fb abfdge fgdca fedcag bafcgd bfg gdeabfc fbgac eagcb bcdf | gacfedb fb bf fcadg
+bg eadgf bcdea gbd gebda edgbac cagb dfecab fgcbead ecfbgd | gbedca adfebgc acgb bdg
+adgfce begafc gfeac cde cgabd ed becdfa gfed egfbcda egacd | ed cgeda dfeacb dec
+agefcb gadec gdbafe dg cebafdg dcfg ecagf edg gdeacf ceadb | dgaefc egcadbf cdfg faecg
+fdec gcbdaf bafedc cf dbegac ceabd gbadecf fca gbefa bacfe | fc fdce acf afc
+fdecg gdefcba cg dbcfe dfbeac gcfedb daefg facdgb gebc cfg | begafdc fcdebag dbcgaef gfc
+adcgef agbdfec dc ecad cgeabf edfbg bcdgaf fdgce ceagf cdg | cdgef ecda cade cd
+abdefc bdaecfg dgeacb fb gfade bacde bdagcf fdb becf adbef | fcbadg cefabd fdb edfga
+efcgab bead fcdeg ae cgdab dgcbae aeg edgca bcegdaf gdcfab | gdafceb ea eag aeg
+dceafb befac fca cf fdcb cadgef bedaf ebagc aedfbg acgdbef | beadfc cf cfeba gbeca
+gce eacgbd afcdbe eg dfcebga bedca gfbca agfedc gcaeb gebd | gdbe ge ge gbde
+bcgae bedgfca gde ed gdaec gbfcad cgbdef gdaecf edfa gfadc | cdbfeg bgdfac cfdeag adgfbc
+gebca dbacfeg dbfeag bagfe eadfb gf fdge fbg dfceba gafbdc | egfd fedg egafb gf
+begfadc bdcae dgbca edbf acbfeg fcgead be eba afdce aedcbf | bfedac edcab eba fdbace
+fdbgc cegabf ac dfbage bgfae faec gac caedbg bfgedca bfagc | acef dfgcb face gbafed
+cdbfge bfceg dgacbe baegfd ecb dfceabg ebdfg cb acfge bdfc | cbe gcbefd egdcba eafbdg
+fecdb dgbcfae bedca edf ef cfebgd ecgf gfdbc fdbagc afbged | aedbgf ef fecg fagcbd
+gdecfb fbadge cabe adfcg efcbd ea gbeacfd fcedba dea fdeac | acbe acbe dea fcgedba
+bg dgfac gabdec dgcabef beafc gfceab cgb bafcde fegb cgafb | bcg bg fdgca faebcg
+adfgc dfcbge dgafbc gaf acfb dgcea gebcdaf fbgdea fbgdc af | fa agcdf fga gfebda
+defag begdf fa becgda aef afcg dfaceg cgdae eacdfb acefbgd | cadfeb edgaf fa ecadbf
+fec edfbc fagecd cgdfb ef fcabdg cedba fbecdg bfge faegbcd | befdc dbfecga acgdbf gcbedfa
+ed cedbfg bdfac fdeac baed fde eagcbdf abgfdc feadbc gaefc | fdbca de cgbdfe de
+fcbga ge cagbef acebfdg egbf acbge ceg egcdfa bagdcf adcbe | cgfab ecg ebcda afgcde
+df fadcbeg gcfbde dcagb fbd afgdbc cbeagd dfcab cafbe adfg | eagdbcf fgda cgbda gbfced
+agef bgdcaef ade adcbf gdbace cefdg febgdc cgefda fedca ae | ae afdgec febgcd agcdeb
+gfbc fdg dbaef fg aefgdcb gefdac gebcd dbegac fegcbd fbedg | cfgb gdebc cbaefdg fgd
+ebfgac gcf geabdfc cegbda fgade bcaeg fcba cf fdecgb ecafg | cfg fgc acfgdeb gdabfec
+gafeb ebdgac ed cgbfad cgeadfb bdecfa bfcda fabde aed ecdf | bgfdaec fedcbag de fedc
+age ebcdfg afcdeg dcfeg efadgbc fgad becad ag eacgd gabecf | ag gcdfbe agecd fdgce
+aecfbd geb afbde fdgeab gfeba ebgcadf bg gdbf fgeac bceagd | eacdgfb bge edabcf ebdaf
+cgabe aefbcdg fagdce abcdfg dcbe aecgbd cge fbaeg ce dcbga | bgacfed gafcdb egc egc
+bdefa fagbd fabdce cdae fceagb deb fbdecg fcbea de agedbcf | fgdcabe afbde bde gfcbde
+dgfcea dcbea dabcf edcbga cedafb gfabc cgdabfe afd fd dbfe | debf egdacb dbef edabcg
+bfdea adfceb fgcbae feg fdebg bagfdce egcdb fedagb dgaf gf | bgdfea gef cdebfag edcbgaf
+ade aefgdc ea feac gefdc eacbdfg eabfgd abcdg efbdgc geacd | eafgdc fgebad cbdefg cdefg
+egfdab edfb agfec dbcage ade ed badcfg gfcdeba afedg fgadb | aedbcg bgfda aed dae
+cfdbge abgc afgbe cb bcf ebfdga adecf efbacdg agfbce bacfe | bfc fbc cfb bfc
+gd bgd gcafeb dfcbage ebfgcd egfbd decg gcafdb aedfb ebgfc | gdec gefbacd gdce dg
+gf dbegac becgadf dfge facbe gfa acdgfe ecgfa dcfbag gceda | gfed cefba cabfe acedfg
+fd cdbagef fdgbec daebcg dfba fbacdg cdf cfadg gabdc gfcae | agecf cfd cdf egcbad
+dfca adgefb fbced cfdbge fa egcabfd eabcf eabfcd cabeg afe | acfd dbecf af af
+agfdec dfcag edgacfb baegfd fd gfaecb dacgb ecfga dfec daf | gabcd ebcgadf fbegac fgace
+edafg gcfea cbaeg afcdgbe fcde fc acf cedagf begfda cdbfag | cf daecbfg bgace dcgabef
+bdefagc gcba bfacde adbce ga dgefc cagdeb dgeabf aegdc adg | faecdgb gda ag dga
+becdag bceadf edcab dgacb bdgcaef gd dga cedg agbfc dafebg | gd gced gad cgabd
+gbfaed bdacf db fcabg ecfda edcb adcfge adb abcfed cgedfba | bad dba fdecgab edacf
+ae cabe ecgafb dfgce afbdge gdacfb bdegfca afe agfcb cegfa | ae fgdeab gcfed cgdfabe
+ad fdbcg cbfea fdabgec dca cgadfe fbdac dbag gbcfde bgcfad | dbagfc dac ad cbfdge
+fdgbaec ab dabe cabegd cgaed bcdag bgfdc gebcfa agb cadefg | efbgac dcgafe dagecb gba
+cafbge gdbfac aefcb adfcegb daefc bacge gcabed febg fb bfc | bfcgae gebf bfc abgcdf
+dfbgca bfcae ebc ebfdac eb eadfgcb dfeb edbagc fdcba gfcea | becadf ecb bce badcf
+cdefa adcgfe fdceb eacdfbg adf ad fcgea deag gacbfd aecfgb | da dega adcebfg acdbefg
+dace dcebg adbcfg abdcg de dceagb fcbeg fbacedg bdeafg deb | bed cabgd ed fecbg
+edabgc fdbaegc gcadfe afed fcd gecbf fd fgdcab fedcg dgace | gaecd bdgcaf gedfcab fead
+gfbae bgefdc cbfgdae dbgfea abgc bc aecbgf adfce bce afbce | aedgfbc bacgfe bcdefg gfbea
+cadeg cagdfb bdc bfcedga cgbafe facbe efbd edcba bafdec bd | dbc agdce efdacb bcd
+ac fegacb bac afdc aedfbc defba dgefba gcdeb edacb dcbeagf | egdbc egcfbad decba adfc
+bcfdag cgfdbea dce gbcfd ed bgced dfbgec gcaeb fcbead dgfe | defg edc gecdb de
+eb fbe afdec bfgda cdfbgae fbgcde aedbfc deafgc ecab efdba | aegcdf fedgcab edcfbag be
+cfabg aceg gba fcebda egabfc cbaef acfbdeg ga gcfdb adbfge | cgae abg gace dfabec
+fabe af fdaeg bdega fdceg adbfge fad gcedbfa dfgbac aedgbc | afdgceb aebf dfa cgbaed
+ecgdf bfcagd dcegb gafdc efac feadbgc agcdef eagbfd fge ef | ef egf dcgfa decgf
+ag ecbga bga fdegab gbdcfe gbecf afbecg ebdac edacgfb cagf | gafc ecgbf bag eadgbf
+dafe fe cef agdebfc fecdg bedcg bdcafg beafcg dcegaf fdcag | dafe fcdag afdgce adef
+gefac dagcfe age facdegb acfbg edfa ea edfcg egdcab fcbgde | gcefa ea aebdgc ecfga
+cdfbea debgca adbec bgfadc cdg ceadg bgce gc gfaed fcdgeab | cg cgd afdcbg cdg
+gcbefda fdcga cfdebg fgdabc abgd fdbcg cabfde fda efagc ad | dgcfa bacfed cfbegd da
+cgbaed bcdefg ebdca dcabf feabcdg cgae deabg ced ec efgdba | bgdfce ceag cde dbegac
+debgfa gbdce ecdgbf ag agdc bga acdgbfe bceag cbaef cebagd | bga ga gaceb abecgd
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+bag gceb cbafd bg bgfaec dfgcae cbagf gceaf dfageb bcafegd | agb gb gb fedbagc
+gadce gecdf cgf egbfd beagfc afdc dfcageb cf bcgdae dgefca | fc gfc eacfdg cgf
+dabcfg ebadf cf cebag fbc eagfcb bcegad fgce eabcf ebcgdaf | feacbdg ebadf adfbe fc
+ad fgeac afd bfagcde afbcde gdca debgf adgfe fbagec cfaged | adcg adgefc ad adgcef
+fcdbeag fdbage cadf daecb bgecd bafce bda ad cdbaef eacbgf | ad caebdf gbcefa bcade
+efbgca cabdgef fabcd dafec bf afdgcb fab agcbd fgbd dgceab | fba fb dcagb dbfcag
+bea cbfag agefdc cdeb gbadcef aefgdb eagdc cgdeba egbac be | bgace eb be cbde
+acbdeg cefda fb cfbaeg ebf aefcb gbfc ceagb cegbfda gebafd | agcfbe afdec fbgc dfcegab
+bc cgdab gbfcad ecbdfa cbd fgdac edfacgb dgaeb afecdg bcgf | fcbg dbc dcafgb bcgf
+aedf dga cgfbde fgbde cfbgad dabegf cfgabde geacb bdaeg da | dfea agd baecg gcaeb
+gc cefga dbefac bacedg afedg afcbe becgaf bcgf bdgfeac cag | cgbf bgcf dabceg gc
+db cdegf gcbfd afgbc dgcfba cbgaef dgba fgebacd fadcbe fdb | fgebac bd fdegc db
+debgafc dacbeg fdg cgdba fdagcb eacfg bdcf gafbde fd dcagf | fbcd bgcefda cafbged dfbc
+fcab gdbef begadc fdecga abdcefg bafgec cb cbe efbgc egacf | bce gcfeb cgbfade cbaf
+aedg agfebcd abfge fge cdbefg eg dgcfba gdebfa acbef gafbd | agdfbc baefc efg gbfea
+cdgab cbfedga eacbgd cf dceafg cadgfb fdc efbdg bcfa fdbgc | dfc fc cdgbf gcbadf
+gce eg edcfagb eacgdb bfegdc cdgaf ecgad cebadf eagb cedab | dcbae cdafg gedacfb ge
+dbeagf gfbda fdebgc gabfdc afbgc cgbea fc cdaf ecadbgf fcb | cfgedb bdagf fc gbecfd
+bdcefg egcfab acedg fcdb fbgeda bec cebdg deacbgf cb ebdfg | bc decbg eacgd bdcf
+dfgeab cegba facbegd edg dfgceb gafcbd edbgc gfcbd dcfe de | bdceg fecd cedf defgcb
+egfb dfgace cfgaebd befac adcgb aeg ge cebag bgface bdacfe | cgbea cgbae cbdgaef afebgc
+de efd efdbg efabdcg fgaceb bfgdc fgabe edgfab ebda degacf | fecagd ed adbe de
+fedbga gc gec gaefd ecagf gecbda bafce cgfead cgdf cadfbeg | gafed gcfd cgfd gcfd
+bedfgca ebfdc acgbfd cfb dfbeg decaf bc dabefc beac aedcgf | debgf efacd cb bc
+edgcba eg dbfga acfgeb cdbea bcfdaeg dcge gdeba dacefb egb | efgdacb cgeafbd gfadb gedc
+bacfde dgcefa eabdf acfebdg afgdbc dba aedfc aebgf db bdce | db afecd agcdfe agfedbc
+dga cgadb cdbge bfgca edab ad cbgade efbcdga afedgc ecfgbd | ad dgecb ad bdgac
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+ea ecgbfda eacb efa facegb bgfea ebfdg gfbac edcgaf gcdfba | gabfe bgfeca ae cabe
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+egcdf ecafg afebdc df dgfa agfecd cfbdgea ecgafb gdceb cfd | cdf cgadef acfgbde defgc
+gbdeacf bfcdg cag acdgf efdbcg ac fagdcb gbfeac bcda edfga | agc gaedf abdc cag
+cfgd edbcfg gfebc begcdfa acebgf ged dbace faedbg gecbd gd | bagefc dgefabc defabg becgf
+gcbe ce ebdfa cae bdcagfe bgdac gdeacb cbdagf dbace caegfd | ec acedb gabcd bcagfed
+efdgba cgabfed ec caef ceagb fbega cbgda ebc afbgec ecbdgf | afegdb gacbd dgefab edafgb
+ecagd bfdec fabdce bda beadc gfeabd bdfeacg afbc gecbfd ba | becdf dcaeg gcdea adb
+cefb cfabdg dbf bfeacd baged bf baefd gaecfd cbfaedg fecda | bf fedac fdgecba bdf
+gce gdbcae fecd efcbgd fbdacg eafbg cefgb cbdfg ec fgdacbe | cge ec bgcfead ceg
+deagfb af efca gfecad dfa bacdg cfdegb fecdg egdacfb dfcag | fdgce af edbgafc fdgce
+fagdce ebd abdegf defba cafebdg eb daefg dfbca ebga defcbg | afdeb eb bde egba
+bafed aecdb fbce cbd gdebafc cfbadg badegf bc ecdfab gecad | dbc dbc badgcfe fdgeba
+fgbec bfacde ge edgcfb cgdbfae fdecga cfbga efg dbge cdfeb | bedfcg eg ge afebdcg
+dcaef ag gcab aeg acedg edgcb efgdacb cgfbed dafgeb agdbec | bedagc bdegc dfcebg adecf
+dcfg abecg bgadc dg fcgbda gadebf cdabfe badcf agd fcdbega | abdfeg gd egbac cabgdf
+dfgebc eabcd efcdb dbecfa dac aegdb ca bcgafed fbac fcadge | ca egcdafb afcbdge eagdb
+ebgdc cbgdfe dcbfae bfagcd gdef cebga bceagfd ecd dfbgc ed | de ed fdegcba edc
+eb feb begdcf efgacb gdbe daecf dgcfb fbdcega cebfd gabcdf | efdbc be afdec efb
+begac fbec bcdafg acb cb fgaebd afegbc gebadcf dagec beafg | adgce fceb cgdeafb cab
+ca cdfagb ebfca ebdcgaf afebg dfbgae cega cebfd fbagce fac | bgedaf cgae gdaecfb egdabcf
+gabfd agfc ecdbfag aefcbd afd af gdabfc bgcfed abedg dcgfb | af bdgcef adgbf gcdafb
+egfda fed dbfga adgefb de gacbdf aefgc aecbfd bdge fdbecga | ed de eacbgdf bdeg
+dbfag cdbfea gfdbec agfedbc gfb bg gabfcd fgeda dbfac acbg | dfbac gcba gb fbgda
+dbcgf gba gdcaeb dgbacfe edfba debgcf cbdgaf afcg ag abfdg | bgafecd edfcgb ag dgfba
+bdfcg acebfg egfbacd gfdcba fbg dagb bg cbdaf cgdfe edfcab | bagd gfebacd efbcda gfb
+cedbf fcabdge cge feagbc dfcge gedb adcgf bdcefg edacfb eg | cbdfe cge efbcad cfagdeb
+cga fgeda ceagd ebcg beadc bgfecad fgdcba gc cagebd dfeabc | cag daebgc cg fcdageb
+fgdc fda aebgd cabfde fd agbecf fdacgbe dbfga cfgba bdgacf | facbg fbdagec fdcg ebafcgd
+gbced efbgca gfebd bdc baecg fcabed dcbgeaf gbedac dc acdg | gfbace cdafbe cbaeg bcd
+afgdec ba dbcge daefg dabeg dfbcage afbd fgdaeb gab cfegab | bcfage bgead ba fgdbcea
+ace dgcaef daegbc bfgeda ecbd degab cgabf ce eagbdfc bcgea | cdgeaf bdgea edcb cae
+cd cadf gfead gdefab dce adcfge degcf cgefb gdfbcae aebcgd | efgdc dce ecd dc
+afdbe ad fgdeb fda aebdcgf bcaefg acbfe fdceab bacd dcagef | afd begfd acfeb fda
+dfg afgedbc cbfga gbdace dbagf fdegab edgacf df befd edgba | dgeba df efbd cfadge
+bdcgaf aebg badfce efagc gdefc cabfeg abgcf ecafbdg afe ae | aegdbcf ageb eagb ebdfgca
+gdceab fb bfe cgbfea edbagfc cafed ebacg ebafc defgcb gbfa | efb efcba bf afgb
+bafcg cdfgb ac caf fcdabe adgc dbgefc bedafcg bgacdf bfaeg | bcfegad afegb gabfdce bgcfa
+dafgb gca fcab fcabgd dcfaebg gfcdae cgdba ac gbadef egcbd | bcedg aebgfcd gfeadb afbc
+adebg fcgaedb dagfe agfc fdbaec fgaecd feg acdfe gf becdgf | feg fge gfe egf
+gf gfda gfb gfcebd gefab afcbged eabdg adgbfe fbace bgcade | dbafgce fbdaeg dagf fcbae
+fbegcd ecg cefdbag fcgd ebdac gbecd cg bfcgea bafdeg edfgb | fcbegd acbde bcgaef cge
+gbcadf cf gfbc defbca acgfd bcaedg afegd cfbgeda caf gcdba | begcad cfa bagfedc gbcdeaf
+begacdf dcafbg gb cgfbed gbcde cedfab dfcbe gbc cadge ebfg | gbfe gb ebcdfga bfeg
+fe bgadefc cbgdf gbfade cefgd ecdgaf efg afce eacgd dcgeab | gdebac fcae egbdfac fgdeab
+ebfca fdac fdb bgdecaf dbcgef cedbfa bgcefa fd eadfb baegd | cgfaeb dgbecf dfb bagecf
+ebda eagcf gcbea ba bfcegad acebgd gdecb cdafgb acb gfcdbe | fgcebd cedbgf gbfdac cefag
+edacf fed eacgd febadc ebafc bfcgea ecafgdb adbf fd gbfdec | fabce egfcbd deafgbc bafd
+gfbe fdbga ged ge aegdf baegcd afecd ebgcfda fgacbd gdeafb | cdfae fdaec ge aefdg
+gebaf afdbcg cfged dga fgead febdcga ad fbaedg bade gbfaec | cgbfdea gadfecb agfde gad
+fdg cfgdbe cfbeadg cgbf gedbc dcfage dfgeb fg agcbed adefb | gdf bdecg faedb gfd
+acdgbe cfabg gfbacd cbf dfbcea bcfegad cf gcdab efbag fdcg | dbfagc fgbdcea cbdga fc
+afbcg dgbfac dgaebf gcfea gbceadf afb fb abgcd abcdge fdcb | gbceda cgdabe bcgdae fbgdea
+cgbedf dbgfc cbef cf bgfda gcedb gadceb efdcag fdc bcfdaeg | fecb ebdcfg cf badgf
+fg cafdg fegadbc aefcdb bcagd degf gfecba adegfc cfg fdeac | gdcafe cgfdae gebfca dfcgae
+fdbecg fcagbd fgeabd cadbe bcdag dafgb facg gdc bdgeacf cg | cedab cbdga gcd gc
+gdeaf edbcag fbac fgecdba dfbcea afdce ac fbecd dbefcg cea | efcbd gdeaf dfceagb ace
+abgdc ebcgd ecgdf ebagcd dabe edgbcfa be cgeabf ceb cdfgba | fdacbg abegcd abdgc cabfdge
+fbgcd feacb ed eadf becfd bde fdabce cgdbea fadbcge gbefac | dcgbf fcebd ebcfd gbface

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/2020/days/day-13.lisp	Wed Dec 08 18:00:32 2021 -0800
@@ -0,0 +1,21 @@
+(advent:defpackage* :advent/2020/13)
+(in-package :advent/2020/13)
+
+(defun parse (stream)
+    (cons (parse-integer (read-line stream))
+            (_ (read-line stream)
+              (str:split "," _)
+              (remove "x" _ :test #'string=)
+              (mapcar #'parse-integer _))))
+
+(defun part1 (n buses)
+  (iterate (for b :in buses)
+           (for wait = (- (mod n (- b))))
+           (finding (* b wait) :minimizing wait)))
+
+(define-problem (2020 13) (data parse) (174)
+  (destructuring-bind (n . buses) data
+      (values (part1 n buses))))
+
+
+#; Scratch --------------------------------------------------------------------

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/2021/days/day-08.lisp	Wed Dec 08 18:00:32 2021 -0800
@@ -0,0 +1,93 @@
+(advent:defpackage* :advent/2021/08
+  (:import-from :alexandria :length= :set-equal))
+
+(in-package :advent/2021/08)
+
+;;   0 . a b c   e f g   6
+;;   1 .     c     f     2
+;;   2 . a   c d e   g   5
+;;   3 . a   c d   f g   5
+;;   4 .   b c d   f     4
+;;   5 . a b   d   f g   5
+;;   6 . a b   d e f g   6
+;;   7 . a   c     f     3
+;;   8 . a b c d e f g   7
+;;   9 . a b c d   f g   6
+
+(defun parse (stream)
+  (iterate
+    (for line :in-stream stream :using #'read-line)
+    (for words = (mapcar (rcurry #'coerce 'list) (str:split " " line)))
+    (collect (split-sequence:split-sequence '(#\|) words :test #'equal))))
+
+(defun input (entry) (first entry))
+(defun output (entry) (second entry))
+
+(defun uniquep (word)
+  (member (length word) '(2 3 4 7)))
+
+(defun supersetp (sup sub)
+  (and (subsetp sub sup)
+       (null (set-difference sub sup))))
+
+(defun common-element (&rest sets)
+  (let ((result (reduce #'intersection sets)))
+    (assert (length= 1 result) () "No common element in ~S." sets)
+    (first result)))
+
+(defun solve-entry (entry)
+  (let ((words (remove-duplicates (append (input entry) (output entry))
+                                  :test #'set-equal))
+        (solved (list))) ; alist of e.g. (1 . (#\a #\b))
+    (flet ((solve (n predicate)
+             (let ((result (find-if predicate words)))
+                (alexandria:deletef words result :test #'set-equal)
+                (push (cons n result) solved))))
+      ;; * 1, 4, 7, 8 have unique lengths.
+      (solve 1 (curry #'length= 2))
+      (solve 4 (curry #'length= 4))
+      (solve 7 (curry #'length= 3))
+      (solve 8 (curry #'length= 7))
+      ;; * 9 is a superset of 4.
+      (solve 9 (rcurry #'supersetp (assocdr 4 solved)))
+      ;; * 0 is the 6-element superset of 7.
+      (solve 0 (lambda (word) (and (supersetp word (assocdr 7 solved)) (length= 6 word))))
+      ;; * 3 is the 5-element superset of 7.
+      (solve 3 (lambda (word) (and (supersetp word (assocdr 7 solved)) (length= 5 word))))
+      ;; * 6 is the only 6-element group left.
+      (solve 6 (curry #'length= 6))
+      ;; * 5 contains the only element all the solved so far have in common.
+      (solve 5 (lambda (word)
+                 (member (apply #'common-element (mapcar #'cdr solved))
+                         word)))
+      ;; * 2 is the last one left.
+      (solve 2 (constantly t))
+      ;; Return the result.
+      (digits->number
+        (loop :for o :in (output entry)
+              :collect (rassocar o solved :test #'set-equal))))))
+
+(defun part1 (entries)
+  (iterate (for entry :in entries)
+           (summing (count-if #'uniquep (output entry)))))
+
+(defun part2 (entries)
+  (summation entries :key #'solve-entry))
+
+(define-problem (2021 8) (data parse) (440 1046281)
+  (values (part1 data)
+          (part2 data)))
+
+
+#; Scratch --------------------------------------------------------------------
+(solve-entry
+  '(((#\a #\b #\c #\e #\f #\g)
+     (#\c #\f)
+     (#\a #\c #\d #\e #\g)
+     (#\a #\c #\d #\f #\g)
+     (#\b #\c #\d #\f)
+     (#\a #\b #\d #\f #\g)
+     (#\a #\b #\d #\e #\f #\g)
+     (#\a #\c #\f))
+    ((#\a #\b #\c #\d #\e #\f #\g)
+     (#\a #\b #\c #\d #\f #\g))))