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15 Oh, hello! Funny seeing you here.
17 I appreciate your enthusiasm, but you aren't going to find much down here.
18 There certainly aren't clues to any of the puzzles. You do risk spoiling a few
19 surprises for yourself, though. Best to play the normal way and discover
20 everything as it was intended, I think. The best surprises don't even appear
21 in the source until you unlock them for real.
23 Please be careful with automated requests; I'm not Google, and I can only take
24 so much traffic. Please be considerate so that everyone gets to play.
26 If you're curious about how Advent of Code works, it's running on some custom
27 Perl code. Other than a few integrations (auth, analytics, ads, social media),
28 I built the whole thing myself, including the design, animations, prose, and
31 The puzzles probably took the longest; the easiest ones were around 45 minutes
32 each, but the harder ones took 2-3 hours, some even longer than that. A lot of
33 effort went into building this thing - I hope you're enjoying playing it as
34 much as I enjoyed making it for you!
36 If you'd like to hang out, I'm @ericwastl on Twitter.
91 <header><h1><a href=
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</a></h1><div class=
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<span class=
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106 <article class=
"day-desc"><h2>--- Day
2: I Was Told There Would Be No Math ---
</h2><p>The elves are running low on wrapping paper, and so they need to submit an order for more. They have a list of the dimensions (length
<code>l
</code>, width
<code>w
</code>, and height
<code>h
</code>) of each present, and only want to order exactly as much as they need.
</p>
107 <p>Fortunately, every present is a box (a perfect
<a href=
"https://en.wikipedia.org/wiki/Cuboid#Rectangular_cuboid">right rectangular prism
</a>), which makes calculating the required wrapping paper for each gift a little easier: find the surface area of the box, which is
<code>2*l*w +
2*w*h +
2*h*l
</code>. The elves also need a little extra paper for each present: the area of the smallest side.
</p>
110 <li>A present with dimensions
<code>2x3x4
</code> requires
<code>2*
6 +
2*
12 +
2*
8 =
52</code> square feet of wrapping paper plus
<code>6</code> square feet of slack, for a total of
<code>58</code> square feet.
</li>
111 <li>A present with dimensions
<code>1x1x10
</code> requires
<code>2*
1 +
2*
10 +
2*
10 =
42</code> square feet of wrapping paper plus
<code>1</code> square foot of slack, for a total of
<code>43</code> square feet.
</li>
113 <p>All numbers in the elves' list are in
<span title=
"Yes, I realize most of these presents are luxury yachts.">feet
</span>. How many total
<em>square feet of wrapping paper
</em> should they order?
</p>
115 <p>Your puzzle answer was
<code>1588178</code>.
</p><article class=
"day-desc"><h2>--- Part Two ---
</h2><p>The elves are also running low on ribbon. Ribbon is all the same width, so they only have to worry about the length they need to order, which they would again like to be exact.
</p>
116 <p>The ribbon required to wrap a present is the shortest distance around its sides, or the smallest perimeter of any one face. Each present also requires a bow made out of ribbon as well; the feet of ribbon required for the perfect bow is equal to the cubic feet of volume of the present. Don't ask how they tie the bow, though; they'll never tell.
</p>
119 <li>A present with dimensions
<code>2x3x4
</code> requires
<code>2+
2+
3+
3 =
10</code> feet of ribbon to wrap the present plus
<code>2*
3*
4 =
24</code> feet of ribbon for the bow, for a total of
<code>34</code> feet.
</li>
120 <li>A present with dimensions
<code>1x1x10
</code> requires
<code>1+
1+
1+
1 =
4</code> feet of ribbon to wrap the present plus
<code>1*
1*
10 =
10</code> feet of ribbon for the bow, for a total of
<code>14</code> feet.
</li>
122 <p>How many total
<em>feet of ribbon
</em> should they order?
</p>
124 <p>Your puzzle answer was
<code>3783758</code>.
</p><p class=
"day-success">Both parts of this puzzle are complete! They provide two gold stars: **
</p>
125 <p>At this point, you should
<a href=
"/">return to your advent calendar
</a> and try another puzzle.
</p>
126 <p>If you still want to see it, you can
<a href=
"/day/2/input" target=
"_blank">get your puzzle input
</a>.
</p>
127 <p>You can also
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