1 files changed, 35 insertions, 0 deletions
diff --git a/2022/Day04/part-one.cl b/2022/Day04/part-one.cl
new file mode 100644
index 0000000..ad422b2
--- /dev/null
+++ b/2022/Day04/part-one.cl
@@ -0,0 +1,35 @@
+(defvar *prog-input*)
+
+;;; After running file, if you enter a blank line, code will work on each
+;;; line of input, until "end" is typed.
+;;; Otherwise, the input is taken as a filename and code will be executed
+;;; over each line in the file until EOF.
+(let ((ui (read-line)))
+  (if (equal ui "")
+    (setq *prog-input* *standard-input*)
+    (setq *prog-input* (open ui))))
+
+(defun fully-overlapping (a b)
+  (or (and (<= (car a) (car b)) (<= (cdr b) (cdr a)))
+      (and (<= (car b) (car a)) (<= (cdr a) (cdr b)))))
+
+(let
+  ((inpt (read-line *prog-input* NIL)) (first-range '()) (second-range '()) (comma 0) (sum 0))
+
+  (loop until (or (string= inpt "end") (not inpt)) do
+        (setq first-range  (cons (parse-integer inpt :junk-allowed T :start 0)
+                                 (parse-integer inpt :junk-allowed T :start (+ 1 (position #\- inpt)))))
+        (setq comma (+ 1 (position #\, inpt)))
+        (setq second-range (cons (parse-integer inpt :junk-allowed T :start comma)
+                                 (parse-integer inpt :junk-allowed T :start (+ 1 (position #\- inpt :start comma)))))
+
+        (if (fully-overlapping first-range second-range)
+          (setq sum (+ 1 sum)))
+
+        (setq inpt (read-line *prog-input* NIL)))
+
+  (print sum))
+
+(if (not (eq *prog-input* *standard-input*))
+  (close *prog-input*))
+