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: Wrong Answer)

import java.util.Scanner;

public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int a = sc.nextInt();
        int b = sc.nextInt();
        
        if(a == 1 && b == 1){
            System.out.println("#");
       }else if(a == 2 && b == 2){
            System.out.println("##\n##");
       }else if(a != 0 && b != 0){
        	StringBuilder buff = new StringBuilder();
        	for(int i= 0; i < b; i++){
            	buff.append("#");
            }
            buff.append("\n");
            
            for(int i= 0; i < a-2; i++){
            	buff.append("#");
            	for(int j = 0; j<b-2; j++){
            		buff.append(".");
            	}
            	buff.append("#\n");
            }
            
            for(int i= 0; i < b; i++){
            	buff.append("#");
            }
            buff.append("\n");
            System.out.println(buff);
        }
    }
}