Problem:
Print a Frame

Draw a frame which has a height of H cm and a width of W cm. For example, the following figure shows a frame which has a height of 6 cm and a width of 10 cm.

##########
#........#
#........#
#........#
#........#
##########

Input

The input consists of multiple datasets. Each dataset consists of two integers H and W separated by a single space.

The input ends with two 0 (when both H and W are zero).

Output

For each dataset, print the frame made of '#' and '.'.

Print a blank line after each dataset.

Constraints

3 ≤ H ≤ 300

3 ≤ W ≤ 300

Sample Input

3 4
5 6
3 3
0 0

Sample Output

####
#..#
####

######
#....#
#....#
#....#
######

###
#.#
###

Solution in Scala (judge verdict: Accepted)

import scala.io.StdIn

/**
  * AOJ
  */
object Main {

  def main(args: Array[String]): Unit = {

    while(true) {
      val in = StdIn.readLine().split(" ").map(_.toInt)
      val H = in(0)
      val W = in(1)
      if(H == 0 && W == 0) return
      for(i <- 1 to H;j <- 1 to W){
        print(
          (i,j) match {
          case (1,_) | (_,1) | (H,_) | (_,W)=> "#"
          case _ => "."
          }
        )
        if(j == W){println()}
      }
      println()
    }
  }
}