From 308d83c0f4a1dcc4085b3b7bcc25892c8b0b1f74 Mon Sep 17 00:00:00 2001 From: Correl Roush Date: Tue, 15 Dec 2015 12:53:33 -0500 Subject: [PATCH] Day 8: Matchsticks --- advent-of-code.org | 388 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 388 insertions(+) diff --git a/advent-of-code.org b/advent-of-code.org index 921931f..4f7da80 100644 --- a/advent-of-code.org +++ b/advent-of-code.org @@ -3720,3 +3720,391 @@ signal is ultimately provided to wire =a=? #+RESULTS[61e8544d7d4f32d111e9a666de842ecc4248e390]: : 40149 +* Day 8: Matchsticks +Space on the sleigh is limited this year, and so Santa will be +bringing his list as a digital copy. He needs to know how much space +it will take up when stored. + +It is common in many programming languages to provide a way to escape +special characters in strings. For example, C, JavaScript, Perl, +Python, and even PHP handle special characters in very similar ways. + +However, it is important to realize the difference between the number +of characters *in the code representation of the string literal* and +the number of characters *in the in-memory string itself*. + +For example: + +- =""= is =2= characters of code (the two double quotes), but the + string contains zero characters. +- ="abc"= is =5= characters of code, but 3 characters in the string + data. +- ="aaa\"aaa"= is =10= characters of code, but the string itself + contains six ="a"= characters and a single, escaped quote character, + for a total of =7= characters in the string data. +- ="\x27"= is =6= characters of code, but the string itself contains + just one - an apostrophe (='=), escaped using hexadecimal notation. + +Santa's list is a file that contains many double-quoted string +literals, one on each line. The only escape sequences used are =\\= +(which represents a single backslash), =\"= (which represents a lone +double-quote character), and =\x= plus two hexadecimal characters +(which represents a single character with that ASCII code). + +Disregarding the whitespace in the file, what is *the number of +characters of code for string literals* minus *the number of +characters in memory for the values of the strings* in total for the +entire file? + +For example, given the four strings above, the total number of +characters of string code =(2 + 5 + 10 + 6 = 23)= minus the total +number of characters in memory for string values =(0 + 3 + 7 + 1 = +11)= is =23 - 11 = 12=. + +---------------------------------------------------------------------- + +:HIDDEN: +#+name: 8-input +#+BEGIN_EXAMPLE + "qxfcsmh" + "ffsfyxbyuhqkpwatkjgudo" + "byc\x9dyxuafof\\\xa6uf\\axfozomj\\olh\x6a" + "jtqvz" + "uzezxa\"jgbmojtwyfbfguz" + "vqsremfk\x8fxiknektafj" + "wzntebpxnnt\"vqndz\"i\x47vvjqo\"" + "higvez\"k\"riewqk" + "dlkrbhbrlfrp\\damiauyucwhty" + "d\"" + "qlz" + "ku" + "yy\"\"uoao\"uripabop" + "saduyrntuswlnlkuppdro\\sicxosted" + "tj" + "zzphopswlwdhebwkxeurvizdv" + "xfoheirjoakrpofles\"nfu" + "q\xb7oh\"p\xce\"n" + "qeendp\"ercwgywdjeylxcv" + "dcmem" + "\"i\x13r\"l" + "ikso\xdcbvqnbrjduh\"uqudzki\xderwk" + "wfdsn" + "pwynglklryhtsqbno" + "hcoj\x63iccz\"v\"ttr" + "zf\x23\\hlj\\kkce\\d\\asy\"yyfestwcdxyfj" + "xs" + "m\"tvltapxdvtrxiy" + "bmud" + "k\"a" + "b\"oas" + "\"yexnjjupoqsxyqnquy\"uzfdvetqrc" + "vdw\xe3olxfgujaj" + "qomcxdnd\"\\cfoe\"" + "fpul" + "m\"avamefphkpv" + "vvdnb\\x\\uhnxfw\"dpubfkxfmeuhnxisd" + "hey\\" + "ldaeigghlfey" + "eure\"hoy\xa5iezjp\\tm" + "yygb\"twbj\\r\"\x10gmxuhmp\"" + "weirebp\x39mqonbtmfmd" + "ltuz\\hs\"e" + "ysvmpc" + "g\x8amjtt\"megl\"omsaihifwa" + "yimmm" + "iiyqfalh" + "cwknlaaf" + "q\x37feg\xc6s\"xx" + "uayrgeurgyp\\oi" + "xhug\"pt\"axugllbdiggzhvy" + "kdaarqmsjfx\xc3d" + "\"vkwla" + "d\"" + "tmroz\"bvfinxoe\\mum\"wmm" + "\"n\"bbswxne\\p\\yr\"qhwpdd" + "skzlkietklkqovjhvj\xfe" + "pbg\\pab\"bubqaf\"obzcwxwywbs\\dhtq" + "xxjidvqh\"lx\\wu\"ij" + "daef\x5fe\x5b\\kbeeb\x13qnydtboof" + "ogvazaqy\"j\x73" + "y" + "n\"tibetedldy\\gsamm\"nwu" + "wldkvgdtqulwkad" + "dpmxnj" + "twybw\"cdvf\"mjdajurokbce" + "ru\"\\lasij\"i" + "roc\\vra\\lhrm" + "pbkt\x60booz\"fjlkc" + "j\x4dytvjwrzt" + "\\uiwjkniumxcs" + "cbhm\"nexccior\"v\"j\"nazxilmfp\x47" + "qdxngevzrlgoq" + "\"lrzxftytpobsdfyrtdqpjbpuwmm\x9e" + "mdag\x0asnck\xc2ggj\"slb\"fjy" + "wyqkhjuazdtcgkcxvjkpnjdae" + "aixfk\xc0iom\x21vueob" + "dkiiakyjpkffqlluhaetires" + "ysspv\"lysgkvnmwbbsy" + "gy\"ryexcjjxdm\"xswssgtr" + "s" + "ddxv" + "qwt\"\x27puilb\"pslmbrsxhrz" + "qdg\xc9e\\qwtknlvkol\x54oqvmchn\\" + "lvo" + "b" + "fk\"aa\"\"yenwch\\\\on" + "srig\x63hpwaavs\\\x80qzk\"xa\"\xe6u\\wr" + "yxjxuj\"ghyhhxfj\"\xa6qvatre" + "yoktqxjxkzrklkoeroil" + "\"jfmik\"" + "smgseztzdwldikbqrh\"" + "jftahgctf\"hoqy" + "tcnhicr\"znpgckt\"ble" + "vqktnkodh\"lo\"a\\bkmdjqqnsqr" + "ztnirfzqq" + "s" + "xx" + "iqj\"y\\hqgzflwrdsusasekyrxbp\\ad" + "\\xzjhlaiynkioz\"\"bxepzimvgwt" + "s\x36rbw" + "mniieztwrisvdx" + "atyfxioy\x2b\\" + "irde\x85\x5cvbah\\jekw\"ia" + "bdmftlhkwrprmpat\"prfaocvp" + "w\\k" + "umbpausy" + "zfauhpsangy" + "p\"zqyw" + "wtztypyqvnnxzvlvipnq\"zu" + "deicgwq\\oqvajpbov\\or\"kgplwu" + "mbzlfgpi\\\\zqcidjpzqdzxityxa" + "lfkxvhma" + "\xf2yduqzqr\"\\fak\"p\"n" + "mpajacfuxotonpadvng" + "anb\\telzvcdu\\a\xf2flfq" + "lrs\"ebethwpmuuc\"\x86ygr" + "qmvdbhtumzc\"ci" + "meet" + "yopg\x0fdxdq\"h\\ugsu\xffmolxjv" + "uhy" + "fzgidrtzycsireghazscvmwcfmw\\t" + "cqohkhpgvpru" + "bihyigtnvmevx\"xx" + "xz" + "zofomwotzuxsjk\"q\"mc\"js\"dnmalhxd" + "\\ktnddux\\fqvt\"ibnjntjcbn" + "ia" + "htjadnefwetyp\xd5kbrwfycbyy" + "\"\\hkuxqddnao" + "meqqsz\x83luecpgaem" + "cvks\x87frvxo\"svqivqsdpgwhukmju" + "sgmxiai\\o\"riufxwjfigr\xdf" + "fgywdfecqufccpcdn" + "faghjoq\x28abxnpxj" + "zuppgzcfb\"dctvp\"elup\"zxkopx" + "xqs\x45xxdqcihbwghmzoa" + "anbnlp\\cgcvm\"hc" + "xf\"fgrngwzys" + "nrxsjduedcy\x24" + "\x71sxl\"gj\"sds\"ulcruguz\\t\\ssvjcwhi" + "jhj\"msch" + "qpovolktfwyiuyicbfeeju\x01" + "nkyxmb\"qyqultgt\"nmvzvvnxnb" + "ycsrkbstgzqb\"uv\\cisn" + "s" + "ueptjnn\"\"sh" + "lp\"z\"d\"mxtxiy" + "yzjtvockdnvbubqabjourf\"k\"uoxwle" + "\x82\"wqm\"" + "\xb5cwtuks\x5fpgh" + "wd" + "tbvf" + "ttbmzdgn" + "vfpiyfdejyrlbgcdtwzbnm" + "uc" + "otdcmhpjagqix" + "\\\xb1qso\"s" + "scowax" + "behpstjdh\xccqlgnqjyz\"eesn" + "r\xe1cbnjwzveoomkzlo\\kxlfouhm" + "jgrl" + "kzqs\\r" + "ctscb\x7fthwkdyko\"\x62pkf\"d\xe6knmhurg" + "tc\"kw\x3ftt" + "bxb\x5ccl" + "jyrmfbphsldwpq" + "jylpvysl\"\"juducjg" + "en\\m\"kxpq\"wpb\\\"" + "madouht\"bmdwvnyqvpnawiphgac\"" + "vuxpk\"ltucrw" + "aae\x60arr" + "ttitnne\"kilkrgssnr\xfdurzh" + "oalw" + "pc\"\"gktkdykzbdpkwigucqni\"nxiqx" + "dbrsaj" + "bgzsowyxcbrvhtvekhsh\"qgd" + "kudfemvk\"\"\"hkbrbil\"chkqoa" + "zjzgj\\ekbhyfzufy" + "\\acos\"fqekuxqzxbmkbnn\x1ejzwrm" + "elxahvudn\"txtmomotgw" + "\x2eoxmwdhelpr\"cgi\xf7pzvb" + "eapheklx" + "hfvma\"mietvc\"tszbbm\"czex" + "h\"iiockj\\\xc1et" + "d\"rmjjftm" + "qlvhdcbqtyrhlc\\" + "yy\"rsucjtulm\"coryri\"eqjlbmk" + "tv" + "r\"bfuht\\jjgujp\"" + "kukxvuauamtdosngdjlkauylttaokaj" + "srgost\"\"rbkcqtlccu\x65ohjptstrjkzy" + "yxwxl\\yjilwwxffrjjuazmzjs" + "dxlw\\fkstu\"hjrtiafhyuoh\"sewabne" + "\x88sj\"v" + "rfzprz\xec\"oxqclu\"krzefp\\q" + "cfmhdbjuhrcymgxpylllyvpni" + "ucrmjvmimmcq\x88\xd9\"lz" + "lujtt\"" + "gvbqoixn\"pmledpjmo\"flydnwkfxllf" + "dvxqlbshhmelsk\x8big\"l" + "mx\x54lma\x8bbguxejg" + "\x66jdati\xeceieo" + "\"iyyupixei\x54ff" + "xohzf\"rbxsoksxamiu" + "vlhthspeshzbppa\x4drhqnohjop\"\"mfjd" + "f\"tvxxla\"vurian\"\"idjq\x3aptm\xc3olep" + "gzqz" + "kbq\\wogye\\altvi\\hbvmodny" + "j\xd8" + "ofjozdhkblvndl" + "hbitoupimbawimxlxqze" + "ypeleimnme" + "xfwdrzsc\\oxqamawyizvi\\y" + "enoikppx\xa1ixe\"yo\"gumye" + "fb" + "vzf" + "zxidr" + "cu\x31beirsywtskq" + "lxpjbvqzztafwezd" + "\\jyxeuo\x18bv" + "b\"vawc\"p\\\\giern\"b" + "odizunx\"\"t\\yicdn\"x\"sdiz" + "\"\"tebrtsi" + "ctyzsxv\xa6pegfkwsi\"tgyltaakytccb" + "htxwbofchvmzbppycccliyik\xe5a" + "ggsslefamsklezqkrd" + "rcep\"fnimwvvdx\"l" + "zyrzlqmd\x12egvqs\\llqyie" + "\x07gsqyrr\\rcyhyspsvn" + "butg\"" + "gb" + "gywkoxf\"jsg\\wtopxvumirqxlwz" + "rj\"ir\"wldwveair\x2es\"dhjrdehbqnzl" + "ru\"elktnsbxufk\\ejufjfjlevt\\lrzd" + "\"widsvok" + "oy\"\x81nuesvw" + "ay" + "syticfac\x1cfjsivwlmy\"pumsqlqqzx" + "m" + "rjjkfh\x78cf\x2brgceg\"jmdyas\"\\xlv\xb6p" + "tmuvo\"\x3ffdqdovjmdmkgpstotojkv\"as" + "jd\\ojvynhxllfzzxvbn\"wrpphcvx" + "pz" + "\"twr" + "n\\hdzmxe\"mzjjeadlz" + "fb\"rprxuagvahjnri" + "rfmexmjjgh\\xrnmyvnatrvfruflaqjnd" + "obbbde\"co\"qr\"qpiwjgqahqm\\jjp\"" + "vpbq\"\"y\"czk\\b\x52ed\"lnzepobp" + "syzeajzfarplydipny\"y\"\xe8ad" + "mpyodwb" + "\x47rakphlqqptd" + "wa\"oj\"aiy" + "a" + "ropozx" + "q\x51nbtlwa" + "etukvgx\\jqxlkq" + "\"tp\"rah\"pg\"s\"bpdtes\\tkasdhqd" + "dn\"qqpkikadowssb\xcah\"dzpsf\\ect\"jdh" + "pxunovbbrrn\\vullyn\"bno\"\"\"myfxlp\"" + "qaixyazuryvkmoulhcqaotegfj\\mpzm" + "bvfrbicutzbjwn\\oml\"cf\"d\"ezcpv\"j" + "rmbrdtneudemigdhelmb" + "aq\\aurmbhy" + "wujqvzw" + "gf\"tssmvm\"gm\"hu\x9a\xb7yjawsa" + "hrhqqxow\xe2gsydtdspcfqy\"zw\\ou" + "ianwwf\\yko\\tdujhhqdi" + "xylz\"zpvpab" + "lwuopbeeegp" + "aoop\x49jhhcexdmdtun" + "\\\\mouqqcsgmz" + "tltuvwhveau\x43b\"ymxjlcgiymcynwt" + "gsugerumpyuhtjljbhrdyoj" + "lnjm\xb8wg\"ajh" + "zmspue\"nfttdon\\b\"eww" + "\"w\x67jwaq\x7ernmyvs\\rmdsuwydsd\"th" + "ogtgvtlmcvgllyv" + "z\"fqi\"rvddoehrciyl" + "yustxxtot\"muec\"xvfdbzunzvveq" + "mqslw" + "txqnyvzmibqgjs\xb6xy\x86nfalfyx" + "kzhehlmkholov" + "plpmywcnirrjutjguosh\\" + "pydbnqofv\"dn\\m" + "aegqof" + "eambmxt\\dxagoogl\\zapfwwlmk" + "afbmqitxxqhddlozuxcpjxgh" + "vgts" + "bfdpqtoxzzhmzcilehnflna" + "s\"idpz" + "\xcfhgly\"nlmztwybx\"ecezmsxaqw" + "aackfgndqcqiy" + "\x22unqdlsrvgzfaohoffgxzfpir\"s" + "abh\"ydv\"kbpdhrerl" + "bdzpg" + "ekwgkywtmzp" + "wtoodejqmrrgslhvnk\"pi\"ldnogpth" + "njro\x68qgbx\xe4af\"\\suan" +#+END_EXAMPLE +:END: + +#+BEGIN_SRC emacs-lisp :var input=8-input :exports both + (defun day8/hex-replacements (string-literal) + (-map (lambda (escaped-hex) + (let ((hex-code (string-to-number (substring escaped-hex 2) 16))) + (cons escaped-hex (char-to-string hex-code)))) + (-map #'car (s-match-strings-all "\\\\x[0-9,a-f][0-9,a-f]" string-literal)))) + + (defun day8/parse-string (string-literal) + (let ((contents (substring string-literal 1 -1))) + (-reduce-from + (lambda (acc replacement) + (s-replace (car replacement) + (cdr replacement) + acc)) + contents + (append '(("\\\"" . "\"") + ("\\\\" . "\\")) + (day8/hex-replacements contents))))) + + (ert-deftest day8/parse-string () + (should (string-equal "" + (day8/parse-string "\"\""))) + (should (string-equal "abc" + (day8/parse-string "\"abc\""))) + (should (string-equal "aaa\"aaa" + (day8/parse-string "\"aaa\\\"aaa\""))) + (should (string-equal "'" + (day8/parse-string "\"\\x27\"")))) + + + (let* ((code-strings (split-string input "\n" t)) + (string-values (-map #'day8/parse-string code-strings))) + (- (-sum (-map #'length code-strings)) + (-sum (-map #'length string-values)))) +#+END_SRC + +#+RESULTS[acaa7a9432ace3b411d0bfcd4c61620b43ce21c5]: +: 1350 +