def square(n):
    for i in range(n):
        for j in range(n):
            print '#',
        print


def empty_square(n):
    for i in range(n):
        for j in range(n):
            if i == 0 or i == n - 1 or j == 0 or j == n - 1:
                print '#',
            else:
                print ' ',
        print


def diagonal_square(n):
    for i in range(n):
        for j in range(n):
            if (i == 0 or i == n - 1 or j == 0 or j == n - 1 or
                    i == j or n - i - 1 == j):
                print '#',
            else:
                print ' ',
        print


def arrow_square(n):
    for i in range(n):
        for j in range(n):
            if (i == 0 or i == n - 1 or j == 0 or j == n - 1 or
                    (n - i - 1 >= j and i >= j)):
                print '#',
            else:
                print ' ',
        print