diff --git a/2017/ruby/day_17.rb b/2017/ruby/day_17.rb
new file mode 100644
index 0000000..c3f4ff2
--- /dev/null
+++ b/2017/ruby/day_17.rb
@@ -0,0 +1,21 @@
+input = ARGF.read.strip.to_i
+# input = 3
+
+# buffer = [0]
+pos = 0
+50_000_000.times do |i|
+# 10.times do |i|
+  pos += input + 1
+  # pos %= buffer.size
+  pos %= i + 1
+
+  p i+1 if pos.zero?
+
+  # buffer = (buffer[0..pos] << i+1).concat(buffer[pos+1..-1])
+end
+
+# index = buffer.index(0)
+# p buffer[index+1]
+
+# So 0 is always element 0...
+# So we just need to know when something is inserted at element 1?