What have you tried so far? What do you think the steps might be, if you break both problems down? Can you use a solution to the first problem to solve the second?

The second question cannot be answered without knowing by which criteria you consider "[11,15]" to be an array of integers. Like is it meant to be json formatted, elixir code, anything else?

Considering double quotes as part of the string, below might work

`
def test(data) when is_binary(data), do: true

def test(data) when is_list(data) do
data
|> Enum.all?(&is_integer/1)
end

`

For the string, you can return a tuple indicating the type. Sorry; typing from a phone.