object Main extends App {
    val N = scala.io.StdIn.readInt
    val A = scala.io.StdIn.readLine.split(" ").map(_.toInt).toList
    val B = scala.io.StdIn.readLine.split(" ").map(_.toInt).toList
    val C = scala.io.StdIn.readLine.split(" ").map(_.toInt).toList

    val point = B.sum

    var index: Seq[Int] = Nil
    for (n <- 1 to N - 1) {
      if (A(n) - A(n - 1) == 1) {
        index = index :+ n
      }
    }
    val bonus = index.map { x => C(x) }.sum

    val answer = point + bonus

    println(point + bonus)
}