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);
        while(true) {
            int h = sc.nextInt();
            int w = sc.nextInt();

            if(h == 0 && w == 0) {
                break;
            }

            for(int i=0; i<h; i++) {
                StringBuilder sb = new StringBuilder();
                for(int j=0; j<w; j++) {
                    if(i == 0 || i == h-1) {
                        sb.append("#");
                    } else if(j == 0 || j == w-1) {
                        sb.append("#");
                    } else if(j != 0 && j != w-1) {
                        sb.append(".");
                    }
                }
                System.out.println(sb);
            }
            System.out.println("");
        }
        sc.close();
    }
}