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.*;
//import java.lang.Math;
public class Main{
    public static void main(String[] args){
        Scanner sc=new Scanner(System.in);
        while(true){
            int a=sc.nextInt();
            int b=sc.nextInt();
            if(a==0 && b==0) break;
            for(int i=0;i<a;i++){
                for(int j=0;j<b;j++){
                    if(i!=0 && i!=a-1 && j!=0 && j!=b-1) System.out.print(".");
                    else System.out.print("#");
                }
                System.out.println();
            }
            System.out.println();
        }
        sc.close();
    }
}