a=list(map(int,input().split()))
n=a[0]
m=a[1]
for  i in range(0,n):
   if (i==0 or i==n-1):
     for  j in range(0,m):
         print("*",end="")
     print()
   else:
     for j in range(0,m):
       if (j==0 or j==m-1
           ):
            print("*",end="")
       else:
            print(" ",end="")
     print()