import java.util.Scanner

object Main {
  def main(args: Array[String]) {
    val result = solve(new Scanner(System.in))
    if (result.length > 0) println(result)
  }

  def solve(in: String): String = solve(new Scanner(in))

  def solve(sc: Scanner): String = {
    val N = sc.nextInt
    val ST = Array.fill(2)(sc.next)

    ST(0).zipWithIndex.map {
      case (s: Char, i: Int) => "%c%c".format(s, ST(1)(i))
    }.mkString("")
  }
}
