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;
 
class Main {
    @SuppressWarnings("resource")
    public static void main(String[] args) {
        StringBuilder sb=new StringBuilder("");
         
        Scanner n=new Scanner(System.in);
         
        int a=n.nextInt();
        int b=n.nextInt();
         
        while (a!=0 || b!=0){
            for (int c = 0; c < a ; c++){
                for (int d = 0 ; d < b ; d++){
                    if(c == 0 || c == a - 1 || d == 0 || d == b - 1){
                    	sb.append("#");
                    } else{
                    	sb.append(".");
                    }
                }
                sb.append("\n");
                 
            }
            System.out.println(sb);
            a=n.nextInt();
            b=n.nextInt();
            sb=new StringBuilder("");
        }
    }
}