object Main extends App {
    import scala.annotation.tailrec

    val sc = new java.util.Scanner(System.in)
    val pw = new java.io.PrintWriter(System.out)
    @tailrec
    def output(h: Int = sc.nextInt, w: Int = sc.nextInt): Unit = {
        if( h != 0 && w != 0 ) {
            pw.println("#"*w)
            for(i <- 1 to h-2) pw.println("#"+"."*(w-2)+"#")
            pw.println("#"*w)
            pw.println()
            output()
        }
    }

    output()
    pw.flush
}
