2016-12-03 17:08:20 +00:00
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Advent of Code
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--- Day 3: Squares With Three Sides ---
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2018-03-15 16:24:23 +00:00
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Now that you can think clearly, you move deeper into the labyrinth of
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hallways and office furniture that makes up this part of Easter Bunny HQ.
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This must be a graphic design department; the walls are covered in
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specifications for triangles.
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2016-12-03 17:08:20 +00:00
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Or are they?
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2018-03-15 16:24:23 +00:00
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The design document gives the side lengths of each triangle it describes,
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but... 5 10 25? Some of these aren't triangles. You can't help but mark the
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impossible ones.
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2016-12-03 17:08:20 +00:00
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2018-03-15 16:24:23 +00:00
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In a valid triangle, the sum of any two sides must be larger than the
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remaining side. For example, the "triangle" given above is impossible,
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because 5 + 10 is not larger than 25.
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2016-12-03 17:08:20 +00:00
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In your puzzle input, how many of the listed triangles are possible?
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2018-03-15 16:24:23 +00:00
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Your puzzle answer was 869.
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2016-12-03 17:08:20 +00:00
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The first half of this puzzle is complete! It provides one gold star: *
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--- Part Two ---
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2018-03-15 16:24:23 +00:00
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Now that you've helpfully marked up their design documents, it occurs to you
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that triangles are specified in groups of three vertically. Each set of
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three numbers in a column specifies a triangle. Rows are unrelated.
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2016-12-03 17:08:20 +00:00
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2018-03-15 16:24:23 +00:00
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For example, given the following specification, numbers with the same
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hundreds digit would be part of the same triangle:
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2016-12-03 17:08:20 +00:00
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101 301 501
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102 302 502
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103 303 503
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201 401 601
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202 402 602
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203 403 603
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2018-03-15 16:24:23 +00:00
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In your puzzle input, and instead reading by columns, how many of the listed
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triangles are possible?
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2016-12-03 17:08:20 +00:00
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2018-03-15 16:24:23 +00:00
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Your puzzle answer was 1544
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2016-12-03 17:08:20 +00:00
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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/2016/about
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. http://adventofcode.com/2016/support
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. http://adventofcode.com/2016/events
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. http://adventofcode.com/2016/settings
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. http://adventofcode.com/2016/auth/logout
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. http://adventofcode.com/2016
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. http://adventofcode.com/2016
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. http://adventofcode.com/2016/leaderboard
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. http://adventofcode.com/2016/stats
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. http://adventofcode.com/2016/sponsors
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. http://adventofcode.com/2016/sponsors
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. http://adventofcode.com/2016/day/3/input
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