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 soto=new StringBuilder("");
		StringBuilder naka=new StringBuilder("");
		int H=sc.nextInt(),W=sc.nextInt();
	while(H!=0||W!=0){
			soto.append("##");
		naka.append("#");
		for(int n=1;n<=W-2;n++){
			naka.append(".");
			soto.append("#");}
		naka.append("#");
		System.out.println(soto);
		for(int n=1;n<=H-2;n++){
			System.out.println(naka);}
		System.out.println(soto+"\n");
		soto.delete(0,W);naka.delete(0,W);
		H=sc.nextInt();W=sc.nextInt();
			}
	}}