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diff --git a/AoC2023/day08/solver.lisp b/AoC2023/day08/solver.lisp
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+(ql:quickload '(fiveam str))
+                                        ;12:13
+                                        ;
+(defparameter eg-input "LLR
+
+AAA = (BBB, BBB)
+BBB = (AAA, ZZZ)
+ZZZ = (ZZZ, ZZZ)")
+
+(defun parse-input (lines)
+  (let ((graph (make-hash-table)))
+    (destructuring-bind (instructions blank . nodes) lines
+      (declare (ignorable blank))
+      (dolist (line nodes)
+        (with-input-from-string (in (str:replace-all "=|," "" line :regex t))
+          (setf
+           (gethash (read in) graph)
+           (read in))))
+      (values instructions graph))))
+
+(defun traverse (instructions graph location steps)
+  (if (eq location 'ZZZ)
+      (values steps location)
+      (let ((new-steps (loop
+                         for direction across instructions
+                         do
+                            (setf location
+                                  (ecase direction
+                                    (#\L (first (gethash location graph)))
+                                    (#\R (second (gethash location graph)))))
+                         count direction until (eq location 'ZZZ))))
+        (traverse instructions graph location (+ steps new-steps)))))
+
+(defun solver1 (lines)
+  (multiple-value-bind (instructions graph)
+      (parse-input lines)
+    (traverse instructions graph 'AAA 0)))
+
+(fiveam:test solutions
+  (fiveam:is (= 6 (solver1 (uiop:split-string eg-input :separator '(#\Newline)))))
+  (fiveam:is (= 19199 (solver1 (uiop:read-file-lines "input")))))