advent_of_code/2019/day04_secure_container/challenge.txt

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You arrive at the Venus fuel depot only to discover it's protected by a password. The Elves had written the password on a sticky note, but someone threw it out.
However, they do remember a few key facts about the password:
* It is a six-digit number.
* The value is within the range given in your puzzle input.
* Two adjacent digits are the same (like `22` in `1*22*345`).
* Going from left to right, the digits *never decrease*; they only ever increase or stay the same (like `111123` or `135679`).
Other than the range rule, the following are true:
* `111111` meets these criteria (double `11`, never decreases).
* `2234*50*` does not meet these criteria (decreasing pair of digits `50`).
* `123789` does not meet these criteria (no double).
*How many different passwords* within the range given in your puzzle input meet these criteria?
Your puzzle answer was `921`.
\--- Part Two ---
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An Elf just remembered one more important detail: the two adjacent matching digits *are not part of a larger group of matching digits*.
Given this additional criterion, but still ignoring the range rule, the following are now true:
* `112233` meets these criteria because the digits never decrease and all repeated digits are exactly two digits long.
* `123*444*` no longer meets the criteria (the repeated `44` is part of a larger group of `444`).
* `111122` meets the criteria (even though `1` is repeated more than twice, it still contains a double `22`).
*How many different passwords* within the range given in your puzzle input meet all of the criteria?
Your puzzle answer was `603`.
Both parts of this puzzle are complete! They provide two gold stars: \*\*
At this point, you should [return to your Advent calendar](/2019) and try another puzzle.
Your puzzle input was `278384-824795`.