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;

namespace KitaSoftKoubouEnshuuMondai
{
    class Program
    {
        static void Main(string[] args)
        {

            while (true)
            {
                string[] data = Console.ReadLine().Split(' ');
                int H = int.Parse(data[0]), W = int.Parse(data[1]);

                if (H == 0 && W == 0) break;

                for (int i = 0; i < H; i++)
                {
                    for (int j = 0; j < W; j++)
                        Console.Write((i == 0 || i == H - 1 || j == 0 || j == W - 1) ? '#' : '.');
                    Console.WriteLine();
                }
                Console.WriteLine();
            }
        }
    }
}