How to read from STDIN in Elixir (for HackerRank) by uxjp

1_read_from_input.ex

defmodule Solution do
    input_as_int = elem(Integer.parse(IO.gets(nil)), 0)
    1..input_as_int |> Enum.each(fn _ -> IO.puts "Hello World" end)
end

2_only_pipes.ex

defmodule Solution do
    IO.gets(nil)
        |> String.trim
        |> String.to_integer
        |> (fn(x) -> Range.new(1, x) end).()
        |> Enum.each(fn _ -> IO.puts("Hello World") end)
end

3_use_&_shorthand.ex

defmodule Solution do
    IO.gets(nil)
        |> String.trim
        |> String.to_integer
        |> (&(Range.new(1, &1))).()
        |> Enum.each(fn _ -> IO.puts("Hello World") end)
end

4_closure

defmodule Solution do
  inn = IO.gets(nil)
  
  
  fufu = inn 
  |> String.trim
  |> String.to_integer
  |> (&(Range.new(1, &1))).()
  |> Enum.each(fn _ -> IO.puts("Hello World") end)
  
  fufu.()
end
# this don't work in hacker rank as a valid answer but is a good exemple of closure.
# Now the most interesting use I can imagine for a closure is
# as a value returned by a function, where the returned closure captures a
# state, hiding how some information was obtained.