## \-\-- 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 pass*word*. 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?*

Your puzzle answer was `383`.

## \-\-- Part Two \-\-- {#part2}

For added security, [yet another system
policy]{title="Because as everyone knows, the number of rules is proportional to the level of security."}
has been put in place. Now, a valid passphrase must contain no two words
that are anagrams of each other - that is, a passphrase is invalid if
any word\'s letters can be rearranged to form any other word in the
passphrase.

For example:

-   `abcde fghij` is a valid passphrase.
-   `abcde xyz ecdab` is not valid - the letters from the third word can
    be rearranged to form the first word.
-   `a ab abc abd abf abj` is a valid passphrase, because *all* letters
    need to be used when forming another word.
-   `iiii oiii ooii oooi oooo` is valid.
-   `oiii ioii iioi iiio` is not valid - any of these words can be
    rearranged to form any other word.

Under this new system policy, *how many passphrases are valid?*

Your puzzle answer was `265`.

Both parts of this puzzle are complete! They provide two gold stars:
\*\*

At this point, you should [return to your Advent calendar](/2017) and
try another puzzle.

If you still want to see it, you can [get your puzzle
input](4/input).