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 4: The Ideal Stocking Stuffer ---
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2018-03-15 16:24:23 +00:00
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Santa needs help mining some AdventCoins (very similar to bitcoins) to use
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as gifts for all the economically forward-thinking little girls and boys.
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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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To do this, he needs to find MD5 hashes which, in hexadecimal, start with at
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least five zeroes. The input to the MD5 hash is some secret key (your puzzle
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input, given below) followed by a number in decimal. To mine AdventCoins,
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you must find Santa the lowest positive number (no leading zeroes: 1, 2, 3,
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...) that produces such a hash.
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2016-12-16 22:21:15 +00:00
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For example:
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2018-03-15 16:24:23 +00:00
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• If your secret key is abcdef, the answer is 609043, because the MD5 hash
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of abcdef609043 starts with five zeroes (000001dbbfa...), and it is the
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lowest such number to do so.
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• If your secret key is pqrstuv, the lowest number it combines with to
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make an MD5 hash starting with five zeroes is 1048970; that is, the MD5
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hash of pqrstuv1048970 looks like 000006136ef....
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2016-12-16 22:21:15 +00:00
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Your puzzle answer was 282749.
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--- Part Two ---
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Now find one that starts with six zeroes.
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Your puzzle answer was 9962624.
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Both parts of this puzzle are complete! They provide two gold stars: **
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2018-03-15 16:24:23 +00:00
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At this point, you should return to your advent calendar and try another
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puzzle.
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2016-12-16 22:21:15 +00:00
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Your puzzle input was yzbqklnj.
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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/Bitcoin#Mining
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. https://en.wikipedia.org/wiki/Bitcoin
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. https://en.wikipedia.org/wiki/MD5
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. https://en.wikipedia.org/wiki/Hexadecimal
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. http://adventofcode.com/
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