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authorBryan Brattlof <hello@bryanbrattlof.com>2020-12-11 12:25:01 -0500
committerBryan Brattlof <hello@bryanbrattlof.com>2020-12-11 12:25:01 -0500
commita8d67a2eec062b733026bc524811c5448150a216 (patch)
tree0765f008786eefa93a87dee683de5e23c8a2c163
parent9f0b88800f2f8136d53a5ad0cfc8492e51955780 (diff)
downloadadvent-of-code-a8d67a2eec062b733026bc524811c5448150a216.tar.gz
advent-of-code-a8d67a2eec062b733026bc524811c5448150a216.tar.bz2
day01: add questions
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+Day 1: Report Repair
+####################
+
+After saving Christmas five years in a row, you've decided to take a vacation at
+a nice resort on a tropical island. Surely, Christmas will go on without you.
+
+The tropical island has its own currency and is entirely cash-only. The gold
+coins used there have a little picture of a starfish; the locals just call them
+stars. None of the currency exchanges seem to have heard of them, but somehow,
+you'll need to find fifty of these coins by the time you arrive so you can pay
+the deposit on your room.
+
+To save your vacation, you need to get all fifty stars by December 25th.
+
+Collect stars by solving puzzles. Two puzzles will be made available on each day
+in the Advent calendar; the second puzzle is unlocked when you complete the
+first. Each puzzle grants one star. Good luck!
+
+Before you leave, the Elves in accounting just need you to fix your expense
+report (your puzzle input); apparently, something isn't quite adding up.
+
+Specifically, they need you to find the two entries that sum to 2020 and then
+multiply those two numbers together.
+
+For example, suppose your expense report contained the following:
+
+.. code-block:: terminal
+
+ 1721
+ 979
+ 366
+ 299
+ 675
+ 1456
+
+In this list, the two entries that sum to 2020 are 1721 and 299. Multiplying
+them together produces 1721 * 299 = 514579, so the correct answer is 514579.
+
+Of course, your expense report is much larger. Find the two entries that sum to
+2020; what do you get if you multiply them together?
+
+Your puzzle answer was 842016.
+
+Part Two
+########
+
+The Elves in accounting are thankful for your help; one of them even offers you
+a starfish coin they had left over from a past vacation. They offer you a second
+one if you can find three numbers in your expense report that meet the same
+criteria.
+
+Using the above example again, the three entries that sum to 2020 are 979, 366,
+and 675. Multiplying them together produces the answer, 241861950.
+
+In your expense report, what is the product of the three entries that sum to
+2020?
+
+Your puzzle answer was 9199664.
+
+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.
+
+You can also [Share on Twitter Mastodon] this puzzle.