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 Ruby (judge verdict: Accepted)

def draw_frame(h, w)
  h.times do |i|
    if i == 0 || i + 1 == h
      puts "#" * w
    else
      puts "#" + "." * (w - 2) + "#"
    end
  end
end

loop do
  h, w = gets.chomp.split(" ").map(&:to_i)
  if h == 0 && w == 0
    break
  else
    draw_frame(h, w)
    print "\n"
  end
end