day 2 part 1

02a.lisp

@@ -0,0 +1,47 @@
+(require :uiop)
+(load (sb-ext:posix-getenv "ASDF"))
+(asdf:load-system 'str)
+
+(defun get-range (range)
+  (let ((range (str:split "-" range)))
+    (loop for i from (parse-integer (car range)) to (parse-integer (car (cdr range))) collect i)
+    )
+  )
+(get-range "11-22")
+
+(defun get-ranges (instr)
+  (loop for range in
+        (str:split "," (string-trim '(#\Newline) instr))
+        collect
+        (get-range range)
+    )
+  )
+(get-ranges "1-3,4-5")
+
+(defun validate-product-id (product-id)
+  (let ((product-id (format nil "~A" product-id)))
+    (setq product-id-length (length product-id))
+    (setq split-at (/ product-id-length 2))
+    ;(print product-id)
+    (cond
+       ((not (evenp product-id-length)) t)
+       (t (not (string= (subseq product-id 0 split-at) (subseq product-id split-at))))
+      )
+    )
+  )
+(validate-product-id 1212)
+(validate-product-id 123)
+(validate-product-id 1234)
+
+(defun sum-all-invalid-ids (text)
+  (reduce #'+
+    (remove-if #'validate-product-id
+      (reduce #'append
+        (get-ranges text)
+        )
+      )
+    )
+  )
+
+(sum-all-invalid-ids (uiop:read-file-string "02example.txt"))
+(sum-all-invalid-ids (uiop:read-file-string "02data.txt"))