3 files changed, 45 insertions, 13 deletions
diff --git a/AoC2022/04/makefile b/AoC2022/04/makefile
index ee6a716..f4940ca 100644
--- a/AoC2022/04/makefile
+++ b/AoC2022/04/makefile
@@ -10,5 +10,5 @@
 
 run:
 	sbcl --load ~/.sbclrc --script solver.lisp
-	# emacs -batch -l ert -l solver.el -f ert-run-tests-batch-and-exit
+	emacs -batch -l ert -l solver.el -f ert-run-tests-batch-and-exit
 	# rustc solver.rs && ./solver
diff --git a/AoC2022/04/solver.el b/AoC2022/04/solver.el
new file mode 100644
index 0000000..854b247
--- /dev/null
+++ b/AoC2022/04/solver.el
@@ -0,0 +1,29 @@
+(require 'subr-x)
+
+(defun solver-subinterval (a0 a1 b0 b1)
+  "Test if [b0;b1] within [a0;a1]"
+  (and (<= a0 b0 ) (>= a1 b1)))
+
+(defun solver-subcontained (a0 a1 b0 b1)
+  (or (solver-subinterval a0 a1 b0 b1)
+      (solver-subinterval b0 b1 a0 a1)))
+
+(defun solver-overlap (a0 a1 b0 b1)
+  "Test if [b0;b1] overlaps [a0;a1]"
+  (and (<= a0 b1) (<= b0 a1)))
+
+(defun solver-sections-fulfills (func line)
+  (apply func (mapcar #'string-to-number
+                      (split-string line "[,-]"))))
+
+(defun solver-count-according (func)
+  (with-temp-buffer
+    (insert-file-contents "input")
+    (cl-loop for l = (buffer-substring-no-properties (line-beginning-position) (line-end-position))
+             while (not (string-blank-p l))
+             count (solver-sections-fulfills func l)
+             do (forward-line))))
+
+(ert-deftest test-problems ()
+  (should (= 515 (solver-count-according #'solver-subcontained)))
+  (should (= 883 (solver-count-according #'solver-overlap))))
diff --git a/AoC2022/04/solver.lisp b/AoC2022/04/solver.lisp
index 0a4077f..bcf37d7 100644
--- a/AoC2022/04/solver.lisp
+++ b/AoC2022/04/solver.lisp
@@ -4,23 +4,26 @@
   "Test if [b0;b1] within [a0;a1]"
   (and (<= a0 b0 ) (>= a1 b1)))
 
-(defun sections-contained (line)
-  (destructuring-bind (a0 a1 b0 b1)
-      (mapcar #'parse-integer
-              (uiop:split-string line :separator '(#\, #\-)))
-    (or (subinterval a0 a1 b0 b1)
-        (subinterval b0 b1 a0 a1))))
+(defun subcontained (a0 a1 b0 b1)
+  (or (subinterval a0 a1 b0 b1)
+      (subinterval b0 b1 a0 a1)))
 
-(defun count-repeated ()
+(defun overlap (a0 a1 b0 b1)
+  "Test if [b0;b1] overlaps [a0;a1]"
+  (and (<= a0 b1) (<= b0 a1)))
+
+(defun sections-fulfills (function line)
+  (apply function (mapcar #'parse-integer
+                          (uiop:split-string line :separator '(#\, #\-)))))
+
+(defun count-according (function)
   (with-open-file (in "input")
     (loop for l = (read-line in nil nil)
           while l
-          count (sections-contained l))))
-
+          count (sections-fulfills function l))))
 
 (fiveam:test results
-  (fiveam:is (= 515 (count-repeated)))
-  (fiveam:is (= 2567 (badge))))
-
+  (fiveam:is (= 515 (count-according #'subcontained)))
+  (fiveam:is (= 883 (count-according #'overlap))))
 
 (fiveam:run-all-tests)