From cf566277f84028c9cde2bf39da5b6ef2c51d519a Mon Sep 17 00:00:00 2001
From: 4903000 <4903000@chiru.no>
Date: Fri, 4 Dec 2020 18:02:33 +0000
Subject: [PATCH] Day 4

---
 aoc20.lisp | 61 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)

diff --git a/aoc20.lisp b/aoc20.lisp
index 819ca1b..30cb708 100644
--- a/aoc20.lisp
+++ b/aoc20.lisp
@@ -115,3 +115,64 @@
   (time (let ((data (read-3 map)))
 	  (print (solve-3-1 '(1 3) data))
 	  (print (solve-3-2 '((1 1) (1 3) (1 5) (1 7) (2 1)) data)))))
+
+(defvar *passport-fields* (list "byr" "iyr" "eyr" "hgt" "hcl" "ecl" "pid" "cid"))
+(defvar *passport-rules-broken* (list nil nil nil nil nil nil nil (lambda (n) (declare (ignore n)) t)))
+(defvar *passport-rules* nil)
+(setf *passport-rules*
+      (list (lambda (n) (and n (let ((nn (ignore-errors (parse-integer n))))
+				 (and nn (>= nn 1920) (<= nn 2002)))))
+	    (lambda (n) (and n (let ((nn (ignore-errors (parse-integer n))))
+				 (and nn (>= nn 2010) (<= nn 2020)))))
+	    (lambda (n) (and n (let ((nn (ignore-errors (parse-integer n))))
+				 (and nn (>= nn 2020) (<= nn 2030)))))
+	    (lambda (h) (and h (multiple-value-bind (n offset) (parse-integer h :junk-allowed t)
+				 (let ((unit (subseq h offset)))
+				   (cond ((string= unit "cm")
+					  (and (>= n 150) (<= n 193)))
+					 ((string= unit "in")
+					  (and (>= n 59) (<= n 76))))))))
+	    (lambda (c) (and c
+			     (= (length c) 7)
+			     (char= (elt c 0) #\#)
+			     (parse-integer (subseq c 1) :radix 16)))
+	    (lambda (c) (and c (member c '("amb" "blu" "brn" "gry" "grn" "hzl" "oth") :test #'equal)))
+	    (lambda (pid)  (and pid
+				(= 9
+				   (length pid)
+				   (length (remove-if (lambda (n) (not (digit-char-p n))) pid)))))
+	    (lambda (cid) (declare (ignore cid)) t)))
+
+(defun read-passport (stream)
+  (let ((passport-list
+	  (apply #'concatenate 'list 
+		 (loop for line = (read-line stream nil)
+		       while (and line (not (string= line "")))
+		       collect (split-sequence:split-sequence #\space line))))
+	(current-passport (make-hash-table :test 'equal)))
+    (loop for key in passport-list
+	  do (setf (gethash (subseq key 0 3) current-passport)
+		   (subseq key 4)))
+    current-passport))
+
+(defun read-4 (file)
+  (with-open-file (stream file)
+    (loop while (peek-char nil stream nil)
+	  collect (read-passport stream))))
+
+(defun %solve-4 (data tests)
+  (let ((valid-count 0))
+    (loop for passport in data
+	  do (unless (member 'nil
+			      (map 'list (lambda (field test)
+					   (if test
+					       (funcall test (gethash field passport))
+					       (gethash field passport)))
+				   *passport-fields* tests))
+	       (incf valid-count)))
+    valid-count))
+
+(defun solve-4 (file)
+  (let ((data (read-4 file)))
+    (time (progn (print (%solve-4 data *passport-rules-broken*))
+		 (print (%solve-4 data *passport-rules*))))))