1 files changed, 20 insertions, 0 deletions
diff --git a/AoC2022/18/solver.lisp b/AoC2022/18/solver.lisp
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+++ b/AoC2022/18/solver.lisp
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+(ql:quickload '(fiveam uiop))
+
+(defun distance-1 (a b)
+  (apply #'+
+         (mapcar (lambda (e1 e2)
+                   (abs (- e1 e2))) a b)))
+
+(defun surface (cubes)
+  (loop for a in cubes
+        sum (- 6 (loop for b in cubes
+                       count (= 1 (distance-1 a b))))))
+
+(defun parse-coords (filename)
+  (mapcar (lambda (l)
+            (mapcar #'parse-integer (uiop:split-string l :separator ",")))
+          (uiop:read-file-lines filename)))
+
+(fiveam:test solutions
+  (fiveam:is (= 64 (surface (parse-coords "eg-in"))))
+  (fiveam:is (= 4474 (surface (parse-coords "input")))))