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 elevationWithIndex = readLine().split(' ').map(_.toInt).zipWithIndex

  val firstElevationDistance = (averageTemperature(t)(elevationWithIndex.head._1) - a).abs

  val (_, bestElevationIndex) = elevationWithIndex.tail.foldLeft((firstElevationDistance, 0))((minWithIndex, elevationWitchIndex) => {
    val distanceFromA = (averageTemperature(t)(elevationWitchIndex._1) - a).abs
    if (minWithIndex._1 > distanceFromA) (distanceFromA, elevationWitchIndex._2) else minWithIndex
  })

  println(bestElevationIndex + 1)
}