defmodule Main do
  
  def main do
    [h, w] = IO.read(:line) |> String.trim() |> Enum.map(&String.to_integer/1)
    hw = for _ <- 0..(h - 1), do: IO.read(:line) |> String.trim() |> Enum.map(&String.to_integer/1)
    solve(h, w, hw) |> Enum.map(&(Enum.join(&1, " "))) |> Enum.join("\n") |> IO.puts()
  end

  def solve(_h, w, hw) do
    hw |> List.flatten() |> Enum.sort() |> Enum.chunk_every(w)
  end

end