import scala.collection.mutable
import scala.io.StdIn
object Main extends App {
  val N = StdIn.readLine().toInt
  val diametersCount = mutable.Map.empty[Int,Int]
  for (i <- 0 until N; diameter = StdIn.readLine().toInt) {
    if (diametersCount.contains(diameter)) {
      val beforeCount = diametersCount(diameter)
      diametersCount += (diameter -> (beforeCount + 1))
    } else {
      diametersCount += (diameter -> 1)
    }
  }
  println(diametersCount.size)
}
