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 Program
{
    static void Main()
    {
        while(true)
        {
            string[] s = Console.ReadLine().Split(' ');
            int H = int.Parse(s[0]);
            int W = int.Parse(s[1]);
            if (H == 0 && W == 0)
                break;
            for(int i =0;i<H;i++)
            {
                for(int j =0;j<W;j++)
                {
                        if (j==0||j==W-1)
                            Console.Write("#");
                        else
                        {
                            if(i==0||i==H-1)
                                Console.Write("#");
                            else
                                Console.Write(".");
                        }
                }
                Console.WriteLine("");
            }
            Console.WriteLine("");

        }
    }
}