#!/usr/bin/python2
# -*- coding: utf-8 -*-
# †
n = int(raw_input())

def f(i):
    res = 'a' + bin(i)[2:].zfill(18)
    if i == n-1:
        res += 'n'
    else:
        res += 'a'
    return res.replace('0', 'x').replace('1', 'y')

a = [f(i) for i in xrange(n)]
print '\n'.join(a)