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 io.Source.stdin

object Main {

  def main(args: Array[String]) {
    for ((list) <- stdin.getLines().takeWhile(_ != "0 0").map(_.split(" ").map(_.toInt))) {
      val (h: Int, w: Int) = (list(0), list(1))
      printFrame(h, w)
    }
  }

  def printFrame(h: Int, w: Int) {
    for (i <- 1 to h) {
      for (j <- 1 to w) {
        printChar(isEdge(h, w, i, j))
      }
      println()
    }
    println()
  }
  
  def printChar(isEdge: Boolean) {
    if (isEdge) {
      print("#")
    } else {
      print(".")
    }
  }
  
  def isEdge(h: Int, w: Int, i: Int, j: Int): Boolean = {
    if (i == 1 || j == 1 || i == h || j == w) {
      true
    } else {
      false
    }
  }
}