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 C# (judge verdict: Accepted)

using System;using static System.Console;class P{static void Main(){while(1>0){var a=Array.ConvertAll(ReadLine().Split(),int.Parse);if(a[0]+a[1]==0)break;for(int i=0,j;i++<a[0];WriteLine())for(j=0;j++<a[1];Write(i==1||i==a[0]||j==1||j==a[1]?"#":"."));WriteLine();}}}