object Main extends App {
  import scala.io.StdIn.{readInt, readLine}

  val elevationRate = 0.006
  def averageTemperature(T: Double)(elevation: Int) : Double = T - elevation * elevationRate

  val _ = readInt()
  val Array(t, a) = readLine().split(' ').map(_.toInt)
  val elevations = readLine().split(' ').map(_.toInt)

  val distancesFromA = elevations.map(averageTemperature(t)(_) - a)

  println(distancesFromA.zipWithIndex.minBy(_._1.abs)._2 + 1)
}