import scala.io.{StdIn => in}

object Main extends App {
  val out = new java.io.PrintWriter(System.out)
  val n = in.readLine.toInt
  val Array(s, t) = in.readLine.split(" ")

  for(i <- 0 until n)
  {
    out.print(s(i))
    out.print(t(i))
  }

  out.println
  out.flush
}