52 lines
2.6 KiB
Plaintext
52 lines
2.6 KiB
Plaintext
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--- Day 2: Cube Conundrum ---
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You're launched high into the atmosphere! The apex of your trajectory just
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barely reaches the surface of a large island floating in the sky. You gently
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land in a fluffy pile of leaves. It's quite cold, but you don't see much snow.
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An Elf runs over to greet you.
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The Elf explains that you've arrived at Snow Island and apologizes for the lack
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of snow. He'll be happy to explain the situation, but it's a bit of a walk, so
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you have some time. They don't get many visitors up here; would you like to play
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a game in the meantime?
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As you walk, the Elf shows you a small bag and some cubes which are either red,
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green, or blue. Each time you play this game, he will hide a secret number of
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cubes of each color in the bag, and your goal is to figure out information about
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the number of cubes.
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To get information, once a bag has been loaded with cubes, the Elf will reach
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into the bag, grab a handful of random cubes, show them to you, and then put
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them back in the bag. He'll do this a few times per game.
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You play several games and record the information from each game (your puzzle
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input). Each game is listed with its ID number (like the 11 in Game 11: ...)
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followed by a semicolon-separated list of subsets of cubes that were revealed
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from the bag (like 3 red, 5 green, 4 blue).
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For example, the record of a few games might look like this:
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Game 1: 3 blue, 4 red; 1 red, 2 green, 6 blue; 2 green
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Game 2: 1 blue, 2 green; 3 green, 4 blue, 1 red; 1 green, 1 blue
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Game 3: 8 green, 6 blue, 20 red; 5 blue, 4 red, 13 green; 5 green, 1 red
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Game 4: 1 green, 3 red, 6 blue; 3 green, 6 red; 3 green, 15 blue, 14 red
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Game 5: 6 red, 1 blue, 3 green; 2 blue, 1 red, 2 green
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In game 1, three sets of cubes are revealed from the bag (and then put back
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again). The first set is 3 blue cubes and 4 red cubes; the second set is 1 red
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cube, 2 green cubes, and 6 blue cubes; the third set is only 2 green cubes.
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The Elf would first like to know which games would have been possible if the bag
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contained only 12 red cubes, 13 green cubes, and 14 blue cubes?
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In the example above, games 1, 2, and 5 would have been possible if the bag had
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been loaded with that configuration. However, game 3 would have been impossible
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because at one point the Elf showed you 20 red cubes at once; similarly, game 4
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would also have been impossible because the Elf showed you 15 blue cubes at
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once. If you add up the IDs of the games that would have been possible, you get
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8.
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Determine which games would have been possible if the bag had been loaded with
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only 12 red cubes, 13 green cubes, and 14 blue cubes. What is the sum of the IDs
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of those games?
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