#!/usr/bin/python
#-*- coding:UTF-8 -*-
m,n=map(int,raw_input().strip().split())
if (m==1 and n==1):
	print '*'
if (m==1 and n==2):
	print '**'
if (m==2 and n==1):
	print '*'
	print '*'
if (m==2 and n==2):
	print '**'
	print '**'
for i in range(1,m+1):
	if i==1 or i==m:
		print '*'*n
	else :
		print '*'+' '*(n-2)+'*'