43 lines
1.8 KiB
Plaintext
43 lines
1.8 KiB
Plaintext
--- Day 1: Trebuchet?! ---
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Something is wrong with global snow production, and you've been selected to take
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a look. The Elves have even given you a map; on it, they've used stars to mark
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the top fifty locations that are likely to be having problems.
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You've been doing this long enough to know that to restore snow operations, you
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need to check all fifty stars by December 25th.
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Collect stars by solving puzzles. Two puzzles will be made available on each day
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in the Advent calendar; the second puzzle is unlocked when you complete the
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first. Each puzzle grants one star. Good luck!
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You try to ask why they can't just use a weather machine ("not powerful enough")
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and where they're even sending you ("the sky") and why your map looks mostly
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blank ("you sure ask a lot of questions") and hang on did you just say the sky
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("of course, where do you think snow comes from") when you realize that the
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Elves are already loading you into a trebuchet ("please hold still, we need to
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strap you in").
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As they're making the final adjustments, they discover that their calibration
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document (your puzzle input) has been amended by a very young Elf who was
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apparently just excited to show off her art skills. Consequently, the Elves are
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having trouble reading the values on the document.
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The newly-improved calibration document consists of lines of text; each line
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originally contained a specific calibration value that the Elves now need to
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recover. On each line, the calibration value can be found by combining the first
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digit and the last digit (in that order) to form a single two-digit number.
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For example:
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1abc2
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pqr3stu8vwx
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a1b2c3d4e5f
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treb7uchet
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In this example, the calibration values of these four lines are 12, 38, 15, and
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77. Adding these together produces 142.
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Consider your entire calibration document. What is the sum of all of the
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calibration values?
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