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

loop do
  h,w = gets.split.map(&:to_i)
  break if h == 0 && w == 0
  print_frame(h,w)
end