n = gets.to_i
ary = []
x = 50000
while n > 0
  y = x * (x + 1) / 2
  while n >= y
    n -= y
    ary << x
  end
  x -= 1
end
for i in 0 ... ary.size
  print(['a', 'b', 'c'][i % 3] * ary[i])
end
puts()