1 files changed, 108 insertions, 0 deletions
diff --git a/AoC2022/19/solver.lisp b/AoC2022/19/solver.lisp
new file mode 100644
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+++ b/AoC2022/19/solver.lisp
@@ -0,0 +1,108 @@
+(ql:quickload '(fiveam uiop cl-ppcre))
+
+
+(defun material (string)
+  (cond
+    ((string= string "ore") :ore)
+    ((string= string "clay") :clay)
+    ((string= string "obsidian") :obsidian)
+    ((string= string "geode") :geode)))
+
+(defun parse-robot-recipe (line)
+  (cl-ppcre:register-groups-bind ((#'material robot) (#'parse-integer fq) (#'material fm) (#'parse-integer sq) (#'material sm))
+      ("(\\w+) robot costs (\\d+) (\\w+)(?: and (\\d+) (\\w+))?" line)
+    (append
+     (list robot fm fq)
+     (when sm (list sm sq)))))
+
+(defun start-resources ()
+  (list :ore 0 :clay 0 :obsidian 0 :geode 0))
+(defun start-bots ()
+  (list :ore 1 :clay 0 :obsidian 0 :geode 0))
+
+(defun can-build-robot-p (requirements available)
+  (loop for (material amount) on requirements by #'cddr
+        always (<= amount (getf available material 0))))
+
+(defun consume (requirements available)
+  (loop for (material amount) on requirements by #'cddr
+        do (decf (getf available material) amount))
+  available)
+
+(fiveam:test requirements
+  (fiveam:is-false (can-build-robot-p '(:ore 6) '(:ore 5)))
+  (fiveam:is-false (can-build-robot-p '(:ore 6) '(:clay 5)))
+  (fiveam:is-true (can-build-robot-p '(:ore 2) '(:ore 5)))
+  (fiveam:is-true (can-build-robot-p '(:ore 2) '(:clay 2 :ore 5)))
+  (fiveam:is (equal '(:ore 2) (consume '(:ore 3) '(:ore 5)))))
+
+(defun material-collect (bots available-materials)
+  (loop for (material amount) on bots by #'cddr
+        nconc (list material (+ (getf available-materials material 0) amount))))
+
+(defun bot-requirements (type recipes)
+  (cdr (assoc type recipes :test #'eq)))
+
+(defun plist-merge (func p1 p2 &optional default)
+  "Merge 2 flat plists P1 & P2 by FUNC. Use DEFAULT when value is missing on one list."
+  (flet ((keys (plist) (loop for key in plist by #'cddr collect key)))
+    (loop for key in (union (keys p1) (keys p2))
+          nconc (list key (funcall func (getf p1 key default) (getf p2 key default))))))
+
+(defun max-costs (blueprint)
+  (reduce
+   (lambda (acc item)
+     (plist-merge #'max acc item 0))
+   (mapcar #'cdr blueprint)))
+
+(defun can-build (recipes available-materials)
+  (mapcan (lambda (bot-recipes)
+            (when (can-build-robot-p (cdr bot-recipes) available-materials)
+              (list (car bot-recipes))))
+          recipes))
+
+(defun should-build (blueprints robots)
+  (let ((max-cost (max-costs blueprints)))
+    (loop for (type amount) on robots by #'cddr
+          when (or (eq type :geode)
+                   (<= amount (getf max-cost type 0)))
+            collect type)))
+
+(defun try! (build-next robots resources blueprints)
+  (let ((req (bot-requirements build-next blueprints)))
+    (when (can-build-robot-p req resources)
+      (consume req resources)
+      (incf (getf robots build-next 0)))))
+
+
+(defun next-step (build-next robots resources blueprints time-left)
+  (if (zerop time-left)
+      (list robots resources)
+      (let ((new-robots (try! build-next robots resources blueprints)))
+        (mapcar
+         (lambda (next)
+           (next-step next robots (material-collect robots resources) blueprints (1- time-left)))
+         (if new-robots
+             (should-build  blueprints robots)
+             (list build-next))))
+      ))
+
+(let ((blueprints
+        (cdar
+         (mapcar
+          (lambda (l)
+            (let ((blueprint (uiop:split-string l :separator ":.")))
+              (cons (car blueprint)
+                    (mapcar #'parse-robot-recipe (butlast (cdr blueprint))))))
+          (uiop:read-file-lines "eg-in"))))
+      ;; (materials '(:ore 8 :clay 20))
+      (materials (start-resources))
+      (bots (start-bots))
+      ;; (bots '(:geode 1 :ore 8 :clay 20))
+      (time-left 5))
+
+
+  (next-step :clay bots materials blueprints time-left)
+
+
+  )