added check for exact numbers

src/nicethings.rkt

@@ -165,6 +165,7 @@
 (define (rm/remove-nicething item-number)
   (let ([listof-items (file->lines program-path)])
     (if (and (not (null? listof-items))
+             (exact? item-number)
              (>= item-number 0)
              (< item-number (length listof-items)))
       (let* ([item-to-remove (list-ref listof-items item-number)]