main :: IO ()                                                                                                                                         
main = do                                                                                                                                             
  _ <- getLine                                                                                                                                        
  s <- getLine                                                                                                                                        
  k <- readLn :: IO Int                                                                                                                               
  let c = s !! (k-1)                                                                                                                                  
  putStrLn $ map (\x -> if x/=c then '*' else x) s