1 files changed, 12 insertions, 0 deletions
diff --git a/2024/aoc-utils.scm b/2024/aoc-utils.scm
index 7fafcc6..98e83cd 100644
--- a/2024/aoc-utils.scm
+++ b/2024/aoc-utils.scm
@@ -15,3 +15,15 @@
   (map (lambda (line)
          (map string->number (string-split line #\Space)))
        lines))
+
+(define (remove-nth l n)
+  "Remove the `N' element from `L', returning a new list."
+  (append (list-head l n) (list-tail l (1+ n))))
+
+(define (indexes lst)
+  "Get the indexes for `lst'."
+  (let ((retval '()))
+    (do ((i (1- (length lst)) (1- i)))
+        ((< i 0))
+      (set! retval (cons i retval)))
+    retval))