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)

while true do
    h, w = gets.split(" ").map(&:to_i)
    if h && w == 0
        break
    end
    a = h - 2
    b = w - 2

    puts "#" * w 
    i = 0
    while i < a do
        puts ("#" + "." * b + "#")
        i = i + 1
    end
    puts "#" * w
    
    print "\n"
end