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;

	class MainClass
	{
		public static void Main (string[] args)
	{
		while (true) {
			string str = Console.ReadLine ();
			string[] spStr = str.Split (' ');

			int a = int.Parse (spStr [0]);
			int b = int.Parse (spStr [1]);

			if (a == 0 && b == 0) {break;}

			for (int i = 0; i < a; i++) {
				for (int j = 0; j < b; j++) {
					if (i == 0 || i == a - 1 || j == 0 || j == b - 1) {
						Console.Write ("#");
					} else {
						Console.Write (".");
					}
				}
				Console.WriteLine ("");
			}
			Console.WriteLine ("");
		}
	}
}