Clisp 2015 day 2

common_lisp/2015/2/problem.lisp

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+(require :uiop)
+
+(defun input-string () (string-trim '(#\newline) (uiop:read-file-string "../../../data/2015/2/input.txt")))
+
+(defun input-string-list () (uiop:split-string (input-string) :separator (list #\linefeed)))
+
+(defun string-to-dimension-list (string)
+  (mapcar #'parse-integer 
+	  (uiop:split-string string :separator (list #\x))))
+
+(defun dimension-list-to-surface-area (dimension-list)
+  (let ((length (first dimension-list))
+	(width (second dimension-list))
+	(height (third dimension-list)))
+    (+ (* 2 length width) (* 2 length height) (* 2 width height))))
+
+(defun dimension-list-to-slack (dimension-list)
+  (let ((length (first dimension-list))
+	(width (second dimension-list))
+	(height (third dimension-list)))
+    (let ((top (* length width))
+	  (front (* width height))
+	  (side (* length height)))
+      (min top front side))))
+
+(defun dimension-list-to-bow (dimension-list)
+  (let ((length (first dimension-list))
+	(width (second dimension-list))
+	(height (third dimension-list)))
+    (* length width height)))
+
+(defun dimension-list-to-wrap-ribbon (dimension-list)
+  (let ((length (first dimension-list))
+	(width (second dimension-list))
+	(height (third dimension-list)))
+    (let ((top-perim (* 2 (+ length width)))
+	  (front-perim (* 2 (+ width height)))
+	  (side-perim (* 2 (+ length height))))
+      (min top-perim front-perim side-perim))))
+
+(defun dimension-list-to-ribbon (dimension-list)
+  (+ (dimension-list-to-wrap-ribbon dimension-list) (dimension-list-to-bow dimension-list)))
+
+(defun dimension-list-to-paper (dimension-list)
+  (+ (dimension-list-to-surface-area dimension-list) (dimension-list-to-slack dimension-list)))
+
+(defun string-to-paper (string)
+  (dimension-list-to-paper (string-to-dimension-list string)))
+
+(defun string-to-ribbon (string)
+  (dimension-list-to-ribbon (string-to-dimension-list string)))
+
+(defun part-1 ()
+  (reduce (lambda (sfp string)
+	    (+ (string-to-paper string) sfp))
+	  (input-string-list)
+	  :initial-value 0))
+
+(defun part-2 ()
+  (reduce (lambda (sfp string)
+	    (+ (string-to-ribbon string) sfp))
+	  (input-string-list)
+	  :initial-value 0))
+
+(defun solution ()
+  (format t "Part 1: ~a" (part-1))
+  (terpri)
+  (format t "Part 2: ~a" (part-2))
+  (terpri))
+
+(solution)
+