import scala.io.StdIn.readLine

object Main {
  def main(args: Array[String]) {
    def printFrame: Unit = {
      val Array(a, b) = readLine().split(" ").map(_.toInt)
      if(a != 0 && b != 0) {
        for(i <- 1 to a) {
          if(i == 1 || i == a) println("#" * b)
          else println("#" + "." * (b - 2) + "#")
        }
        println()
        printFrame
      }
    }

    printFrame
  }
}