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 System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
public class Test
{
    public static void Main()
    {
        while (true)
        {
            string[] str = Console.ReadLine().Split(' ');
            int h = int.Parse(str[0]);
            int w = int.Parse(str[1]);
            if (h == 0 && w == 0)break;
            
            for(int i= 0; i < h; ++i)
            {
               
                for (int j = 0; j < w; ++j)
                {
                    if (i == 0 || i == h - 1 || j == 0 || j == w - 1)
                    {
                        Console.Write("#");
                    }
                    else
                        Console.Write(".");

                }



                Console.Write("\n");

            }
            Console.Write("\n");
        }
        return ;
    }
}