defmodule Main do
    def main do

        input = IO.binread(:all)

        n = String.to_integer(input)

        x =
            if rem(n, 2) == 0 do
                String.duplicate("1", div(n, 2))
            else
                String.duplicate("1", div(n, 2) - 1) <> "7"
            end |> String.to_integer

        IO.puts x

    end
end