from random import choice
import string

N = int(input())

t = 'a'

for _ in range(N - 1):
    p = [choice(string.ascii_lowercase) for _ in range(19)]
    if p[-1] == 'n':
        p[-1] = 'a'
    print(t + ''.join(p))
    t = p[-1]

print(t + 'n')