aoc 2017 (day 1-6)

www/statics/aoc/2017/04_challenge.txt

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+--- 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?
+
+--- 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?