n,m=map(int,input().split())
if n==1 :
	print ("*"*m)
elif m==1:
	for i in range(0,n):
		print ("*")
else:
	print ("*"*n)
	for i in range(0,m-2):
		 print ("*"+" "*(m-2)+"*")
	print ("*"*n)