diff --git a/2024/ruby/day_11.rb b/2024/ruby/day_11.rb
index 13856ad..cd6e80e 100644
--- a/2024/ruby/day_11.rb
+++ b/2024/ruby/day_11.rb
@@ -6,14 +6,15 @@ blink = Hash.new {|h, k|
            1
          elsif n.zero?
            h[[1, times-1]]
-         elsif (s = n.to_s.size) && s.even?
-           a, b = [n.to_s[0...s/2], n.to_s[s/2..]].map(&:to_i)
+         elsif n.digits.length.even?
+           a, b = n.divmod(10**(d.length/2))
            h[[a, times-1]] + h[[b, times-1]]
          else
            h[[n*2024, times-1]]
          end
 }
 
+pp stones.sum { blink[[_1, 6]] }
 pp stones.sum { blink[[_1, 25]] }
 pp stones.sum { blink[[_1, 75]] }