adventofcode/2017/day04/problem

75 lines
2.3 KiB
Plaintext
Raw Normal View History

2017-12-04 12:49:31 +00:00
Advent of Code
--- 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?
Your puzzle answer was 466.
2017-12-04 12:49:31 +00:00
--- Part Two ---
For added security, yet another system policy 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 251.
2017-12-04 12:49:31 +00:00
Both parts of this puzzle are complete! They provide two
gold stars: **
At this point, you should return to your advent calendar and
try another puzzle.
If you still want to see it, you can get your puzzle input.
References
Visible links
. http://adventofcode.com/
. http://adventofcode.com/2017/about
. http://adventofcode.com/2017/support
. http://adventofcode.com/2017/events
. http://adventofcode.com/2017/settings
. http://adventofcode.com/2017/auth/logout
. http://adventofcode.com/2017
. http://adventofcode.com/2017
. http://adventofcode.com/2017/leaderboard
. http://adventofcode.com/2017/stats
. http://adventofcode.com/2017/sponsors
. http://adventofcode.com/2017/sponsors
. http://adventofcode.com/2017
. http://adventofcode.com/2017/day/4/input