def hoge(h)
    loop {
        s = ""
        18.times do
            s += (rand(26) + ?a.ord).chr
        end
        if !h.has_key?(s)
            h[s] = 1
            return s
        end
   }
end

h = {}
n = gets.to_i
n.times do |i|
    foo = hoge(h)
    if i + 1 == n
        puts "a" + hoge(h) + "n"
    else
        puts "a" + hoge(h) + "a"
    end
end