(*

--- Day 4: High-Entropy Passphrases ---

A new system policy has been put in place that requires all accounts to use a passphrase instead of simply a password. A passphrase consists of a series of words (lowercase letters) separated by spaces.

To ensure security, a valid passphrase must contain no duplicate words.

For example:

    aa bb cc dd ee is valid.
    aa bb cc dd aa is not valid - the word aa appears more than once.
    aa bb cc dd aaa is valid - aa and aaa count as different words.

The system's full passphrase list is available as your puzzle input. How many passphrases are valid?

*)

open Batteries

let validate_passphrase phrase =
    let
        words = String.split_on_char ' ' phrase
    in
        (List.length words) = (words |> Set.of_list |> Set.cardinal)

let parse_input input =
    Enum.map validate_passphrase input
    |> Enum.filter identity
    |> Enum.count

let () =
    Sys.argv.(1)
    |> File.lines_of
    |> parse_input
    |> print_int