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;
using System.Linq;
using System.Text;


namespace PriRect
{
    class Program
    {
        static void Main(string[] args)
        {
            string[] str = new string[2];
            //for(int i = 0; i < str.Length; i++){
            while (true)
            {
                str = Console.ReadLine().Split(' ');
                int height = int.Parse(str[0]);
                int weight = int.Parse(str[1]);
                if ((height == 0) && (weight == 0))
                {
                    break;
                }
                for (int i = 0; i < height; i++)
                {
                    for (int k = 0; k < weight; k++)
                    {
                        if ((i == 0 || i == height - 1 || k == 0 || k == weight - 1))
                        {
                         Console.Write("#");
                        }
                        else
                        {
                            Console.Write(".");
                        }
                     } Console.WriteLine("");
                } Console.WriteLine("");
            }
        }
    }
}