import string
def print_rangoli(size):
    # your code goes here
    n = size
    l1 = list(string.ascii_lowercase)
    x = l1[n - 1::-1] + l1[1:n]
    m = len('-'.join(x))

    for i in range(1, n):
        print('-'.join(l1[n - 1:n - i:-1] + l1[n - i:n]).center(m, '-'))
    for i in range(n, 0, -1):
        print('-'.join(l1[n - 1:n - i:-1] + l1[n - i:n]).center(m, '-'))
