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.Linq;

class Program {
    static void Main() {
        while(true) {
            string[] stdin = Console.ReadLine().Split();
            int h = int.Parse(stdin[0]);
            int w = int.Parse(stdin[1]);
            if((h | w) == 0) break;
            for(int i = 0; i < h; i++) {
                for(int j = 0; j < w; j++) Console.Write(i == 0 || i == h - 1 || j == 0 || j == w - 1? "#" : ".");
                Console.WriteLine();
            }
            Console.WriteLine();
        }
    }
}