src/day04.lisp

   1 (asdf:load-system :adventofcode2020)
   2 (in-package #:adventofcode2020)
   3 (named-readtables:in-readtable :adventofcode2020)
   4
   5 (defun parse-passport (str-list)
   6   (flet ((parser (str)
   7            (->> (split-sequence #\Space str)
   8              (mapcar (fn* (destructuring-bind (a b) (split-sequence #\: _)
   9                             (list (read-from-string a) b)))))))
  10     (mapcan #'parser str-list)))
  11
  12 (defun four-digits-test (pred)
  13   (lambda (s)
  14     (cl-ppcre:register-groups-bind
  15       ((#'parse-integer value)) ("^([0-9]{4})$" s)
  16       (funcall pred value))))
  17
  18 (defparameter *required-field-tests*
  19   (list 'byr (four-digits-test λ(<= 1920 _ 2002))
  20         'iyr (four-digits-test λ(<= 2010 _ 2020))
  21         'eyr (four-digits-test λ(<= 2020 _ 2030))
  22         'hgt λ(cl-ppcre:register-groups-bind
  23                  ((#'parse-integer value) unit) ("^([0-9]+)(in|cm)$" _)
  24                  (cond
  25                    ((string= unit "in") (<= 59 value 76))
  26                    ((string= unit "cm") (<= 150 value 193))
  27                    (t nil)))
  28         'hcl λ(cl-ppcre:scan "^#[0-9a-f]{6}$" _)
  29         'ecl λ(cl-ppcre:scan "^(amb|blu|brn|gry|grn|hzl|oth)$" _)
  30         'pid λ(cl-ppcre:scan "^[0-9]{9}$" _)
  31         'cid (constantly t)))
  32
  33 (defun simple-validate-passport (passport)
  34   (let ((required-fields '(byr iyr eyr hgt hcl ecl pid)))
  35     (every #'identity (mapcar λ(assoc _ passport) required-fields))))
  36
  37 (defun complex-validate-passport (passport)
  38   (flet ((check (pair)
  39                 (destructuring-bind (field value) pair
  40                   (funcall (getf *required-field-tests* field) value))))
  41     (and
  42       (simple-validate-passport passport)
  43       (every #'identity (mapcar #'check passport)))))
  44
  45 (day 04 input
  46   (let ((passports (-<>> (list-from input)
  47                          (split-sequence "" <> :test #'string=)
  48                          (mapcar #'parse-passport))))
  49     (part1 (count t (mapcar #'simple-validate-passport passports)))
  50     (part2 (count t (mapcar #'complex-validate-passport passports)))))
  51
  52 (def-suite day04)
  53 (in-suite day04)
  54
  55 (defvar *passports*
  56              '(("ecl:gry pid:860033327 eyr:2020 hcl:#fffffd"
  57                 "byr:1937 iyr:2017 cid:147 hgt:183cm")
  58                ("iyr:2013 ecl:amb cid:350 eyr:2023 pid:028048884"
  59                 "hcl:#cfa07d byr:1929")
  60                ("hcl:#ae17e1 iyr:2013" "eyr:2024"
  61                 "ecl:brn pid:760753108 byr:1931" "hgt:179cm")
  62                ("hcl:#cfa07d eyr:2025 pid:166559648"
  63                 "iyr:2011 ecl:brn hgt:59in")))
  64
  65 (test parse-passports
  66   (is (equal
  67         '(((ecl "gry") (pid "860033327") (eyr "2020") (hcl "#fffffd") (byr "1937")
  68                        (iyr "2017") (cid "147") (hgt "183cm"))
  69           ((iyr "2013") (ecl "amb") (cid "350") (eyr "2023") (pid "028048884")
  70                         (hcl "#cfa07d") (byr "1929"))
  71           ((hcl "#ae17e1") (iyr "2013") (eyr "2024") (ecl "brn") (pid "760753108")
  72                            (byr "1931") (hgt "179cm"))
  73           ((hcl "#cfa07d") (eyr "2025") (pid "166559648") (iyr "2011") (ecl "brn")
  74                            (hgt "59in")))
  75         (mapcar #'parse-passport *passports*))))
  76
  77 (test simple-validate-passports
  78   (is (equal
  79         '(t nil t nil)
  80         (mapcar (compose #'simple-validate-passport #'parse-passport) *passports*))))
  81
  82 (test passport-field-validators
  83   (flet ((check (pair)
  84            (destructuring-bind (field value) pair
  85              (funcall (getf *required-field-tests* field) value))))
  86     (is-true  (check '(byr "2002")))
  87     (is-false (check '(byr "2003")))
  88
  89     (is-true  (check '(hgt "60in")))
  90     (is-true  (check '(hgt "190cm")))
  91     (is-false (check '(hgt "190in")))
  92     (is-false (check '(hgt "190")))
  93
  94     (is-true  (check '(hcl "#123abc")))
  95     (is-false (check '(hcl "#123abz")))
  96     (is-false (check '(hcl "123abc")))
  97
  98     (is-true  (check '(ecl "brn")))
  99     (is-false (check '(ecl "wat")))
 100
 101     (is-true  (check '(pid "000000001")))
 102     (is-false (check '(pid "0123456789")))))
 103
 104 (defvar *valid-passports*
 105              '(((pid "087499704") (hgt "74in") (ecl "grn") (iyr "2012") (eyr "2030")
 106                                   (byr "1980") (hcl "#623a2f"))
 107                ((eyr "2029") (ecl "blu") (cid "129") (byr "1989") (iyr "2014")
 108                              (pid "896056539") (hcl "#a97842") (hgt "165cm"))
 109                ((hcl "#888785") (hgt "164cm") (byr "2001") (iyr "2015") (cid "88")
 110                                 (pid "545766238") (ecl "hzl") (eyr "2022"))
 111                ((iyr "2010") (hgt "158cm") (hcl "#b6652a") (ecl "blu") (byr "1944")
 112                              (eyr "2021") (pid "093154719"))))
 113
 114 (defvar *invalid-passports*
 115              '(((eyr "1972") (cid "100") (hcl "#18171d") (ecl "amb") (hgt "170")
 116                              (pid "186cm") (iyr "2018") (byr "1926"))
 117                ((iyr "2019") (hcl "#602927") (eyr "1967") (hgt "170cm") (ecl "grn")
 118                              (pid "012533040") (byr "1946"))
 119                ((hcl "dab227") (iyr "2012") (ecl "brn") (hgt "182cm") (pid "021572410")
 120                                (eyr "2020") (byr "1992") (cid "277"))
 121                ((hgt "59cm") (ecl "zzz") (eyr "2038") (hcl "74454a") (iyr "2023")
 122                              (pid "3556412378") (byr "2007"))))
 123
 124 (test complex-validate-passports
 125   (loop for passport in *valid-passports*
 126         do (is-true  (complex-validate-passport passport)))
 127   (loop for passport in *invalid-passports*
 128         do (is-false (complex-validate-passport passport))))
 129
 130 (run! 'day04)