2024/01-2

2024/day-01/stage-2.lisp

@@ -0,0 +1,25 @@
+(require 'asdf)
+
+(asdf:load-system "cl-strings")
+
+(require :cl-strings)
+
+(defun diff (data)
+  (let* ((lists (reduce (lambda (acc itm) (cons (cons (parse-integer (car itm)) (car acc)) (cons (parse-integer (cadr itm)) (cdr acc))))
+                        (mapcar (lambda (line) (cl-strings:split line "   "))
+                                (cl-strings:split data "
+"))
+                        :initial-value (cons (list) (list)))))
+    (reduce (lambda (acc itm)
+              (+ acc (* (car itm) (cdr itm))))
+            (mapcar (lambda (itm) (cons itm (count itm (cdr lists)))) (car lists))
+            :initial-value 0)))
+
+(format t "~s~%" (diff "3   4
+4   3
+2   5
+1   3
+3   9
+3   3"))
+
+(format t "~s~%" (diff (string-right-trim '(#\Space #\Newline) (uiop:read-file-string "input"))))