object Main extends App{
  import java.io.{BufferedOutputStream, BufferedReader, InputStreamReader, PrintWriter}
  val in=new BufferedReader(new InputStreamReader(System.in))
  val out = new PrintWriter(new BufferedOutputStream(System.out))
  val n = in.readLine().toInt
  val m = scala.collection.mutable.HashMap[String,Int]()
  for{i <- ( 1 to n )}{
    val s=in.readLine()
    m(s) = if(m.contains(s)) 0 else 0
  }
  out.println(m.toSeq.size)
  out.flush()
}