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 ConsoleApplication9
{
    class Program
    {
        static void Main(string[] args)
        {
            while (true)
            {
                string Date = Console.ReadLine();
                string[] date = Date.Split(' ');
                int H = int.Parse(date[0]);
                int W = int.Parse(date[1]);

                if (H == 0 && W == 0)       //H,W??±???0????????????
                {
                    break;
                }
                for (int i = 1; i <= H; i++)        
                {
                    for (int j = 1; j <= W; ++j)
                    {
                        if (i == 1 || i == H)       //?§?????????¨?????????
                        {
                            if (j == W)             //????????????
                            {
                                Console.WriteLine("#");
                            }
                            else
                            {
                                Console.Write("#");
                            }
                        }
                        else
                        {
                            if (j == 1 || j == W)
                            {
                                if (j == 1)
                                {
                                    Console.Write("#");
                                }
                                else
                                {
                                    Console.WriteLine("#");
                                }
                            }
                            else
                            {
                                Console.Write(".");
                            }

                        }
                    }
                }
                Console.WriteLine();
            }
        }
    }
}