main :: IO ()
main=readLn>>=putStrLn.umekomi

umekomi :: Int -> String
umekomi n
   | n == 12   = "0.0555555555555555556"
   | n == 18   = "0.0555555555555555556"
   | n == 20   = "0.0555555555555555556"
   | n == 24   = "0.0555555555555555556"
   | n == 30   = "0.0555555555555555556"
   | n == 8    = "0.0277777777777777778"
   | n == 16   = "0.0277777777777777778"
   | n == 27   = "0.0277777777777777778"
   | n == 28   = "0.0277777777777777778"
   | n == 36   = "0.0277777777777777778"
   | n == 40   = "0.0277777777777777778"
   | n == 42   = "0.0277777777777777778"
   | n == 44   = "0.0277777777777777778"
   | n == 45   = "0.0277777777777777778"
   | n == 50   = "0.0277777777777777778"
   | n == 52   = "0.0277777777777777778"
   | n == 56   = "0.0277777777777777778"
   | n == 60   = "0.0277777777777777778"
   | n == 63   = "0.0277777777777777778"
   | n == 66   = "0.0277777777777777778"
   | n == 70   = "0.0277777777777777778"
   | n == 78   = "0.0277777777777777778"
   | n == 84   = "0.0277777777777777778"
   | n == 88   = "0.0277777777777777778"
   | n == 99   = "0.0277777777777777778"
   | n == 104  = "0.0277777777777777778"
   | n == 110  = "0.0277777777777777778"
   | n == 117  = "0.0277777777777777778"
   | n == 130  = "0.0277777777777777778"
   | n == 132  = "0.0277777777777777778"
   | n == 156  = "0.0277777777777777778"
   | otherwise = "0.0000000000000000000"