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;
//using System.Collections.Generic;
//using System.Linq;

namespace problem
{
  class Test
  {
    static void Main()
    {
      while (true)
      {
        var s = Console.ReadLine().Split();
        if (s[0] == "0" && s[1] == "0") break;
        int H = int.Parse(s[0]);
        int W = int.Parse(s[1]);
        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.WriteLine();
        }
        Console.WriteLine();
      }
    }
  }
}