m, n = map(int, input().split())

for i in range(1, m+1):
    if i == 1 or i == m:
        for j in range(1, n+1):
            print("*", end = "")
        print("")
    else:
        print("*", end = "")
        for j in range(1, n-1):
            print(" ", end = "")
        print("*")