2018-03-15 16:24:23 +00:00
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Advent of Code
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2016-12-16 22:21:15 +00:00
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--- Day 14: Reindeer Olympics ---
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2018-03-15 16:24:23 +00:00
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This year is the Reindeer Olympics! Reindeer can fly at high speeds, but
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must rest occasionally to recover their energy. Santa would like to know
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which of his reindeer is fastest, and so he has them race.
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2016-12-16 22:21:15 +00:00
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2018-03-15 16:24:23 +00:00
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Reindeer can only either be flying (always at their top speed) or resting
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(not moving at all), and always spend whole seconds in either state.
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2016-12-16 22:21:15 +00:00
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For example, suppose you have the following Reindeer:
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2018-03-15 16:24:23 +00:00
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• Comet can fly 14 km/s for 10 seconds, but then must rest for 127
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seconds.
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• Dancer can fly 16 km/s for 11 seconds, but then must rest for 162
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seconds.
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2016-12-16 22:21:15 +00:00
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2018-03-15 16:24:23 +00:00
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After one second, Comet has gone 14 km, while Dancer has gone 16 km. After
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ten seconds, Comet has gone 140 km, while Dancer has gone 160 km. On the
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eleventh second, Comet begins resting (staying at 140 km), and Dancer
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continues on for a total distance of 176 km. On the 12th second, both
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reindeer are resting. They continue to rest until the 138th second, when
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Comet flies for another ten seconds. On the 174th second, Dancer flies for
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another 11 seconds.
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2016-12-16 22:21:15 +00:00
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2018-03-15 16:24:23 +00:00
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In this example, after the 1000th second, both reindeer are resting, and
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Comet is in the lead at 1120 km (poor Dancer has only gotten 1056 km by that
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point). So, in this situation, Comet would win (if the race ended at 1000
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seconds).
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2016-12-16 22:21:15 +00:00
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2018-03-15 16:24:23 +00:00
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Given the descriptions of each reindeer (in your puzzle input), after
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exactly 2503 seconds, what distance has the winning reindeer traveled?
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2016-12-16 22:21:15 +00:00
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Your puzzle answer was 2660.
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--- Part Two ---
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2018-03-15 16:24:23 +00:00
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Seeing how reindeer move in bursts, Santa decides he's not pleased with the
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old scoring system.
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2016-12-16 22:21:15 +00:00
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2018-03-15 16:24:23 +00:00
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Instead, at the end of each second, he awards one point to the reindeer
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currently in the lead. (If there are multiple reindeer tied for the lead,
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they each get one point.) He keeps the traditional 2503 second time limit,
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of course, as doing otherwise would be entirely ridiculous.
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2016-12-16 22:21:15 +00:00
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2018-03-15 16:24:23 +00:00
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Given the example reindeer from above, after the first second, Dancer is in
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the lead and gets one point. He stays in the lead until several seconds into
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Comet's second burst: after the 140th second, Comet pulls into the lead and
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gets his first point. Of course, since Dancer had been in the lead for the
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139 seconds before that, he has accumulated 139 points by the 140th second.
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2016-12-16 22:21:15 +00:00
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2018-03-15 16:24:23 +00:00
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After the 1000th second, Dancer has accumulated 689 points, while poor
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Comet, our old champion, only has 312. So, with the new scoring system,
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Dancer would win (if the race ended at 1000 seconds).
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2016-12-16 22:21:15 +00:00
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2018-03-15 16:24:23 +00:00
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Again given the descriptions of each reindeer (in your puzzle input), after
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exactly 2503 seconds, how many points does the winning reindeer have?
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2016-12-16 22:21:15 +00:00
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Your puzzle answer was 1256.
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Both parts of this puzzle are complete! They provide two gold stars: **
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At this point, you should return to your advent calendar and try another puzzle.
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If you still want to see it, you can get your puzzle input.
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References
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Visible links
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. http://adventofcode.com/
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. http://adventofcode.com/about
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. http://adventofcode.com/stats
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. http://adventofcode.com/leaderboard
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. http://adventofcode.com/settings
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. http://adventofcode.com/auth/logout
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. http://adventofcode.com/
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. http://adventofcode.com/day/14/input
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