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diff --git a/src/01.lisp b/src/01.lisp
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+(load "~/quicklisp/setup.lisp")
+(ql:quickload "uiop")
+
+(defun get-file-lines (name)
+  (uiop:read-file-lines name))
+
+;; Turn the input file into whatever form you will use for both parts
+;; (get-file-lines) and (get-file-string) will be useful
+(defun parse-input (input-file)
+  (mapcar 'parse-integer (get-file-lines input-file)))
+
+;; Loops through two item windows on input and counts each time the first is less than the second
+(defun part-a (parsed-input)
+  (let ((sum 0) (prev 0))
+    (dolist (i parsed-input)
+      (if (> i prev) (progn (incf sum 1) (setf prev i))))
+    sum))
+
+;; Similar to part a, but with four item windows, comparing the sum of the first 3 with the next 3
+(defun part-b (parsed-input)
+  (loop for (w x y z) on parsed-input until (null z) if (< (+ w x y) (+ x y z)) count w))
+
+(time (format t "part 1: ~a~%" (part-a (parse-input "../inputs/01.txt"))))
+(time (format t "part 1: ~a~%" (part-b (parse-input "../inputs/01.txt"))))