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;

class Program
{
    static void Main(string[] args)
    {
        string str;
        string[] strer = new string[2];
        var strlist = new List<string>();
        var data = new List<int>();
        int cou = 0;
       
        do
        {
            str = Console.ReadLine();
            if (str == "0 0")
            {
                break;
            }

            strer = str.Split(' ');

            foreach (string s in strer)
            {
                data.Add(int.Parse(s));
            }            
          
        } while (true);

        
        for (int i = 0; i < (data.Count/2); i++)
        {

            for (int j =0; j < data[cou]; j++)
            {
                for (int k = 0; k < data[cou+1]; k++)
                {
                    if ( j != 0 && j != data[cou]-1 && k > 0 && k < data[cou+1]-1 )
                    {
                        Console.Write(".");
                    }
                    else
                    {
                        Console.Write("#");
                    }                 
                }
                Console.Write("\n");
            }
            Console.Write("\n");
            cou += 2;

        }
               
    }
}