import random


n = int(input())
used_words = []

for i in range(n):
    while True:
        word_length = random.choice(range(20))
        if used_words:
            word = used_words[-1][-1] + ''.join([chr(97 + x) for x in random.choices(range(26), k=word_length)])
        else:
            word = ''.join([chr(97 + x) for x in random.choices(range(26), k=word_length)])
        if word[-1] == 'n' or word in used_words or ((i == n-1) and (len(word) == 20)):
            continue
        if i == n-1:
            word += 'n'
        used_words.append(word)
        break

for i in used_words:
    print(i)