local n = io.read("*n")
local a = math.ceil(n / 36)
local rem = n - (a - 1) * 36
local c = 1
local ans = false
for i = 1, 8 do
  for j = i + 1, 9 do
    if c == rem then
      ans = i .. j
      break
    end
    c = c + 1
  end
  if ans then break end
end
ans = ans .. string.rep(ans:sub(2, 2), a - 1)
print(ans)