def duplicateEncode(word: String) = {
    def helper(str:String,i:Int=0,ans:String=""):String=
      {
        if(str.toLowerCase.count(_==str.toLowerCase.charAt(i))>1)
          {
            val strN = ans+")"
            if(i<str.length-1)
              helper(str, i+1, strN)
            else strN
          }
        else {
          val strN = ans+"("
          if(i<str.length-1)
            helper(str, i+1, strN)
          else strN
        }
      }
    helper(word)
  }

/////////////////////////////////////////////////
object Solution {
  def duplicateEncode(word: String) = {
    word.toLowerCase.map(c => if (word.toLowerCase.count(_ == c) <= 1) "(" else ")").mkString
  }
}