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 PrintaFrame
{
	class MainClass
	{
		public static void Main (string[] args)
		{
			while (true)
			{
				string[] data = Console.ReadLine().Split(' ');
				int H = int.Parse(data[0]);
				int W = int.Parse(data[1]);
				if (H == 0 && W == 0)
				{
					return;
				}

				string line = "";
				string line2 = "";
				for (int i = 0,count = W -1; i < W; i++)
				{
					line = line + "#";
					if (i == 0 || i == count)
					{
						line2 = line2 + "#";
					}
					else
					{
						line2 = line2 + ".";
					}
				}

				for (int i = 0,count = H - 1; i < H; i++)
				{
					if (i == 0 || i == count)
					{
						Console.WriteLine(line);
					}
					else
					{
						Console.WriteLine(line2);
					}
				}
				Console.WriteLine();
			}
		}
	}
}