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 1: Not Quite Lisp ---
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2018-03-15 16:24:23 +00:00
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Santa was hoping for a white Christmas, but his weather machine's "snow"
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function is powered by stars, and he's fresh out! To save Christmas, he
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needs you to collect fifty stars by December 25th.
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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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Collect stars by helping Santa solve puzzles. Two puzzles will be made
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available on each day in the advent calendar; the second puzzle is unlocked
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when you complete the first. Each puzzle grants one star. Good luck!
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2016-12-16 22:21:15 +00:00
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Here's an easy puzzle to warm you up.
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2018-03-15 16:24:23 +00:00
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Santa is trying to deliver presents in a large apartment building, but he
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can't find the right floor - the directions he got are a little confusing.
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He starts on the ground floor (floor 0) and then follows the instructions
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one character at a time.
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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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An opening parenthesis, (, means he should go up one floor, and a closing
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parenthesis, ), means he should go down one floor.
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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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The apartment building is very tall, and the basement is very deep; he will
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never find the top or bottom floors.
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2016-12-16 22:21:15 +00:00
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For example:
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• (()) and ()() both result in floor 0.
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• ((( and (()(()( both result in floor 3.
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• ))((((( also results in floor 3.
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• ()) and ))( both result in floor -1 (the first basement level).
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• ))) and )())()) both result in floor -3.
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To what floor do the instructions take Santa?
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Your puzzle answer was 138.
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--- Part Two ---
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2018-03-15 16:24:23 +00:00
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Now, given the same instructions, find the position of the first character
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that causes him to enter the basement (floor -1). The first character in the
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instructions has position 1, the second character has position 2, and so on.
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2016-12-16 22:21:15 +00:00
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For example:
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• ) causes him to enter the basement at character position 1.
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• ()()) causes him to enter the basement at character position 5.
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2018-03-15 16:24:23 +00:00
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What is the position of the character that causes Santa to first enter the
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basement?
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2016-12-16 22:21:15 +00:00
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Your puzzle answer was 1771.
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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/1/input
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