78 lines
3.4 KiB
Plaintext
78 lines
3.4 KiB
Plaintext
Advent of Code
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br0xen 40*
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• [About]
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• [Stats]
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• [Leaderboard]
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• [Settings]
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• [Log out]
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--- Day 2: I Was Told There Would Be No Math ---
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The elves are running low on wrapping paper, and so they need to submit an order for more. They
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have a list of the dimensions (length l, width w, and height h) of each present, and only want
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to order exactly as much as they need.
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Fortunately, every present is a box (a perfect right rectangular prism), which makes
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calculating the required wrapping paper for each gift a little easier: find the surface area of
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the box, which is 2*l*w + 2*w*h + 2*h*l. The elves also need a little extra paper for each
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present: the area of the smallest side.
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For example:
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• A present with dimensions 2x3x4 requires 2*6 + 2*12 + 2*8 = 52 square feet of wrapping
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paper plus 6 square feet of slack, for a total of 58 square feet.
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• A present with dimensions 1x1x10 requires 2*1 + 2*10 + 2*10 = 42 square feet of wrapping
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paper plus 1 square foot of slack, for a total of 43 square feet.
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All numbers in the elves' list are in feet. How many total square feet of wrapping paper should
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they order?
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Your puzzle answer was 1588178.
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--- Part Two ---
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The elves are also running low on ribbon. Ribbon is all the same width, so they only have to
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worry about the length they need to order, which they would again like to be exact.
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The ribbon required to wrap a present is the shortest distance around its sides, or the
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smallest perimeter of any one face. Each present also requires a bow made out of ribbon as
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well; the feet of ribbon required for the perfect bow is equal to the cubic feet of volume of
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the present. Don't ask how they tie the bow, though; they'll never tell.
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For example:
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• A present with dimensions 2x3x4 requires 2+2+3+3 = 10 feet of ribbon to wrap the present
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plus 2*3*4 = 24 feet of ribbon for the bow, for a total of 34 feet.
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• A present with dimensions 1x1x10 requires 1+1+1+1 = 4 feet of ribbon to wrap the present
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plus 1*1*10 = 10 feet of ribbon for the bow, for a total of 14 feet.
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How many total feet of ribbon should they order?
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Your puzzle answer was 3783758.
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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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You can also [Shareon Twitter Google+ Reddit] this puzzle.
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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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. https://en.wikipedia.org/wiki/Cuboid#Rectangular_cuboid
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. http://adventofcode.com/
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. http://adventofcode.com/day/2/input
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. https://twitter.com/intent/tweet?text=I%27ve+completed+%22I+Was+Told+There+Would+Be+No+Math%22+%2D+Day+2+%2D+Advent+of+Code&url=http%3A%2F%2Fadventofcode%2Ecom%2Fday%2F2&related=ericwastl&hashtags=AdventOfCode
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. https://plus.google.com/share?url=http%3A%2F%2Fadventofcode%2Ecom%2Fday%2F2
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. http://www.reddit.com/submit?url=http%3A%2F%2Fadventofcode%2Ecom%2Fday%2F2&title=I%27ve+completed+%22I+Was+Told+There+Would+Be+No+Math%22+%2D+Day+2+%2D+Advent+of+Code
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