import Data.Char

f=g.map((`elem`"yuiophjklnm").toLower)
g(x:y:z)=x/=y&&g(y:z)
g x=x/=[]

main = do
  putStrLn $ show $ f "skepticism"    -- True
  putStrLn $ show $ f "ENDOWMENT"     -- True
  putStrLn $ show $ f "quantity"      -- True
  putStrLn $ show $ f "dispel"        -- True
  putStrLn $ show $ f "kayaks"        -- True
  putStrLn $ show $ f "a"             -- True
  putStrLn ""
  putStrLn $ show $ f "aa"            -- False
  putStrLn $ show $ f "test"          -- False
  putStrLn $ show $ f "WRONG"         -- False
  putStrLn $ show $ f "thiswillfail"  -- False
  putStrLn $ show $ f ""              -- False