n=gets.to_i
if n==1
	puts 'n'
	exit
end
a=(0...26).map{|i|('a'.ord+i).chr*20}
c=''
	i=rand(26)
	s=a[i]
	while s[19]=='n'
		i=random(26)
		s=a[i]
	end
	c=s[19]
	puts s
	a[i].next!
(n-2).times{
	i=c.ord-'a'.ord
	c=a[i][19]
	while c=='n'
		a[i].next!
		c=a[i][19]
	end
	puts a[i]
	a[i].next!
}
i=c.ord-'a'.ord
c=a[i][19]
while c!='n'
	a[i].next!
	c=a[i][19]
end
puts a[i]