adds 2023 day 1 solution

2023/day1.lisp

@@ -0,0 +1,56 @@
+(ql:quickload "cl-ppcre")
+
+(defparameter *digit-map*
+              '(("one" . "1")
+                ("two" . "2")
+                ("three" . "3")
+                ("four" . "4")
+                ("five" . "5")
+                ("six" . "6")
+                ("seven" . "7")
+                ("eight" . "8")
+                ("nine" . "9")))
+
+(defparameter *digit-regex* "one|two|three|four|five|six|seven|eight|nine|0|1|2|3|4|5|6|7|8|9")
+
+(defun parse-number-string (str)
+  (or (cdr (assoc str *digit-map* :test #'string=))
+      (parse-integer str)))
+
+(defun get-calibration-value (line)
+  (parse-integer (format nil "~A~A"
+                   (some #'digit-char-p line)
+                   (some #'digit-char-p (reverse line)))))
+
+(defun get-artistic-calibration-value (line)
+  (parse-integer
+    (format nil "~A~A"
+      (parse-number-string (ppcre:scan-to-strings *digit-regex* line))
+      ;; yuck
+      (parse-number-string
+        (reverse (ppcre:scan-to-strings (reverse *digit-regex*) (reverse line)))))))
+
+(defun part-1 (input)
+  (loop for line in (split-sequence:split-sequence #\newline input)
+          sum (get-calibration-value line)))
+
+(defun part-2 (input)
+  (loop for line in (split-sequence:split-sequence #\newline input)
+          sum (get-artistic-calibration-value line)))
+
+(assert (equal (get-calibration-value "1abc2") 12))
+(assert (equal (get-calibration-value "pqr3stu8vwx") 38))
+(assert (equal (get-calibration-value "a1b2c3d4e5f") 15))
+(assert (equal (get-calibration-value "treb7uchet") 77))
+
+(assert (equal (get-artistic-calibration-value "two1nine") 29))
+(assert (equal (get-artistic-calibration-value "eightwothree") 83))
+(assert (equal (get-artistic-calibration-value "xtwone3four") 24))
+(assert (equal (get-artistic-calibration-value "4nineeightseven2") 42))
+(assert (equal (get-artistic-calibration-value "zoneight234") 14))
+(assert (equal (get-artistic-calibration-value "7pqrstsixteen") 76))
+(assert (equal (get-artistic-calibration-value "eightwo") 82))
+
+(let ((input (string-trim '(#\newline) (uiop:read-file-string "2023/day1.txt"))))
+  (print (part-1 input))
+  (print (part-2 input)))