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 JAVA (judge verdict: Accepted)

import java.util.Scanner;
 
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        StringBuilder Newbuilt = new StringBuilder(); //????????´?????????????????????
      //H??¨W?????\?????????????????????????????§???  
        while (true) {
            String[] array = sc.nextLine().split(" ");
            int H = Integer.parseInt(array[0]);
            int W = Integer.parseInt(array[1]);
            if (H == 0 && W == 0) break ;
      //????????¢?????¢???????¨???????????????¶ HxW
            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)
                        Newbuilt.append("#");
                    else
                        Newbuilt.append(".");

                }
                Newbuilt.append("\n");
            }
            Newbuilt.append("\n");
             
        }
       //StringBuilder????????????????????????????????????????????????????????????
        System.out.print(Newbuilt);
        
        sc.close();
    }
}