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<noinclude>:''This page refers to the comic named "2018". For comic #2018, see [[2018: Wall Art]].''</noinclude>
 
 
{{comic
 
{{comic
 
| number    = 1935
 
| number    = 1935
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==Explanation==
 
==Explanation==
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In this, the first of two [[:Category:New Year|New Year comics]] in a row, [[Megan]] wonders whether 2018 will be a {{w|Leap year|leap year}}. [[Cueball]] thinks 2018 will not be a leap year, and Megan responds that she "doubts anyone knows at this point." This appears to be a jab at people who suggest that anything they don't know is generally unknown. As Cueball says, leap years occur every four years (though there are a few exceptions - a year divisible by 100 is not a leap year, unless it is also  divisible by 400), adding an extra day to account for the fact that Earth takes a bit longer than 365 days to orbit the Sun. Therefore, most years that are a multiple of four are leap years. As Megan says, this is easy for odd-numbered years, since no odd numbers are divisible by four. However, for even-numbered years, it isn't quite as simple. (Though, since the number 2,000 is evenly divisible by 4, the problem can be reduced to the much simpler question of whether the number 18 is divisible by 4.)
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In this comic, [[Megan]] is bizarrely incredulous about basic arithmetic. The dialogue contains several outrageous and blatantly false assertions; we do in fact know that 2018 is ''not'' a leap year, it is easy to accurately determine without guessing that 2018 is evenly divisible by 4 (it's not), and 2018 is not by any stretch a large number when compared to the several-hundred-digit numbers used in modern cryptography. [[Cueball]] seems to be the voice of reason, yet can't seem to formulate a counter-argument against her aggressively stupid statements.
  
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The last panel expresses a misunderstanding of modern public-key {{w|Cryptography|cryptography}}, which relies on the fact that it is difficult to factorize large numbers. Megan is applying this concept to the year, claiming that it is hard to determine whether or not 2,018 is a multiple of four and hence is a leap year. In reality, factorization is not needed here, since we already know the factor in question, which is four. Megan states that, if it were possible to factor large numbers with a calculator, modern cryptography would collapse. While true, it is true only for truly large numbers (hundreds of digits), and no factorization is needed in this case.
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The last panel expresses a misunderstanding of modern cryptography. Modern cryptography relies on the fact that it is extremely difficult and resource-intensive for even top-of-the-line computer farms to factorize large numbers, on the order of hundreds or thousands of digits; moreover, the challenge lies in finding prime factors that themselves are dozens or hundreds of digits long. It is trivial for a human to determine whether an arbitrarily large number is evenly divisible by 4; only the last two digits affect the result. Factoring any four-digit number is also simple, if potentially slightly more time-consuming.
  
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At the end of the strip, Megan hopes the answer can be {{w|Brute-force attack|brute-forced}} by February. Brute force is a method of breaking cryptography by trying every possible option until one works. This is misdirection upon misdirection, in that, even if we needed to factorize 2,018 (which we don't), the simplest brute-forcing algorithm would need to try only 14 numbers -- each prime from 2 to 43 (the square root of 2,018 is closest to 44). In cryptography, the algorithms use numbers much, much bigger than 2,018 -- on the order of hundreds or even thousands of digits.
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At the end of the strip, Megan hopes the answer can be brute-forced by February. Brute force is a method of breaking cryptography by trying every possible option until one works; this is clearly overkill for something as simple as determining whether 2018 is a leap year (which, we'll reiterate, it is not).
  
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The title text refers to calculating which day {{w|Christmas}} will fall on. As Christmas always lands on December 25 by definition, the day of the week varies from year to year, though it's always the 359th or, in leap years, the 360th day of the year. Still, determining which day of the week December 25 lands on is not a difficult problem to solve, requiring only a few mathematical operations to compute. Alternatively, this might be an oblique reference to Easter, the date of which jumps from year to year according to a {{w|Computus|multi-layered algorithm}} that most people don't know. The changing date of Easter was recently included in [[1930: Calendar Facts]]. Additionally, uncertainty with the regard to the date of Christmas has also been referenced in [[679: Christmas Plans]].
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The Gregorian Calendar's leap year system is far from the most complex subject in the world. Leap years occur every four years, adding an extra day to account for the fact that Earth takes a bit longer than 365 days to orbit the Sun. The only exception to the above rule is that, when the year is divisible by 100 but not by 400, it is not a leap year (therefore the years 2100, 2200, 2300, 2500, etc. will not be leap years). With the current state of medical technology, very few humans will encounter the above issue more than once in their lives, and no humans will encounter it more than twice, so it is hardly a great source of confusion for any given person.
  
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A handy coincidence to help with this problem for those living in America or following American politics is that leap years fall on presidential election years.
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The title text contains the bewilderingly idiotic allegation that determining the date of Christmas each year is a resource-intensive group effort. This is especially ludicrous, because {{w|Christmas|Christmas Day always falls on December 25th}}, and this knowledge would not have to be rediscovered each year only to be forgotten the next. Moreover, Megan suggests that the effort to discover Christmas Day lasts until Christmas Day itself; this would imply that Megan is incapable of realizing that Christmas is approaching until the day that it happens. Woe to any friends and family that expect to receive gifts from her.
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Released on Friday, December 29, this is the last comic of 2017. The next scheduled comic will be on New Year's Day of 2018.
  
 
==Transcript==
 
==Transcript==
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{{incomplete transcript|Do NOT delete this tag too soon.}}
  
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:[Megan is walking.]
 
 
:Megan: I wonder if 2018 will be a leap year.
 
:Megan: I wonder if 2018 will be a leap year.
  
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:[Now it turns out that Cueball walks behind Megan.]
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:Cueball: ... It won't be, right?
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:Cueball: ...it won't be, right?
 
 
:Megan: I doubt anyone knows at this point.
 
:Megan: I doubt anyone knows at this point.
  
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:[Same scene in a frame-less panel.]
 
 
:Cueball: No, it's definitely not. Leap years are divisible by 4.
 
:Cueball: No, it's definitely not. Leap years are divisible by 4.
 
:Megan: Right, and for odd numbers, that's easy.  
 
:Megan: Right, and for odd numbers, that's easy.  
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:Megan: 50/50 chance.
 
:Megan: 50/50 chance.
  
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:[Zoomed-out view with both walking in silhouette on a dark slightly curved ground.]
 
 
:Cueball: I can settle this with a calculator.
 
:Cueball: I can settle this with a calculator.
 
:Megan: No way. If it were easy to factor large numbers like that, modern cryptography would collapse.
 
:Megan: No way. If it were easy to factor large numbers like that, modern cryptography would collapse.
 
:Cueball: I see.
 
:Cueball: I see.
 
:Megan: I just hope we manage to brute-force it by February.
 
:Megan: I just hope we manage to brute-force it by February.
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==Trivia==
 
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*Released on Friday, December 29, this was the last comic of 2017. The next comic, [[1936: Desert Golfing]], was released soon after midnight (in Randall's time zone) on New Year's Day 2018.
 
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*Every year that is exactly divisible by four is a leap year, except for years that are exactly divisible by 100, but these centurial years are leap years if they are exactly divisible by 400. For example, the years 1700, 1800, and 1900 were not leap years, but the years 1600 and 2000 were.
 
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*Since 100 is divisible by 4, only the last two digits of a number are needed to determine if that number is divisible by 4. So to determine if 2018 is divisible by 4, we only need to check whether 18 is divisible by 4, which is easy.
 
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*2018 is not divisible by 4, so the year was not a leap year. 2016 and 2020 are leap years. This is true for both the Gregorian and the Julian calendar. A year is roughly 365.2422 days long.
 
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*{{w|Eastern Christian Churches}} celebrate Christmas also on December 25 but on the older Julian calendar, which currently corresponds to January 7 on the Gregorian calendar.
 
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*This is the third year in a row with New Year's comics with only the year used as the title; before that there were two more comics with such titles, but those two (and thus the first three) were only released in the even years: [[998: 2012]] in 2012, [[1311: 2014]] in 2014, [[1624: 2016]] in 2016 and [[1779: 2017]] in 2017.
 
  
 
{{comic discussion}}
 
{{comic discussion}}
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[[Category:New Year]]
 
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[[Category:Comics featuring Megan]]
 
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[[Category:Comics featuring Cueball]]
 
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[[Category:Comics sharing name|2017]]
 
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[[Category:Number theory]]
 
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[[Category:Calendar]]
 
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[[Category:Cryptography]]
 

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