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 Kotlin (judge verdict: Accepted)

fun main(args: Array<String>) {
    while (true){
        val (h, w) = readLine()?.split(" ")?.map { it.toInt() } ?: return
        if (h == 0 && w == 0) return
        for (i in h downTo 1){
            for (j in w downTo 1){
                when{
                    j == 1 -> println("#")
                    i == 1 || i == h || j == w -> print("#")
                    else -> print(".")
                }
            }
        }
        println("")
    }
}