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 Sample{
    static void Main(string[] args){
        while(true){
            string[] a;
            int h,w;
            a = Console.ReadLine().Split(' ');
            h = int.Parse(a[0]);
            w = int.Parse(a[1]);
            if((h==0)&&(w==0)) break;
            for(int i=0; i<h; i++){
                for(int j=0; j<w; j++){
                    if((((i==0)||(i==h-1)) 
                           || ((j==0)||(j==w-1)))){
                        Console.Write("#");
                    } else {
                        Console.Write(".");
                    }
                }
                Console.WriteLine();
            }
            Console.WriteLine();
        }
    }
}