62 lines
2.4 KiB
Plaintext
62 lines
2.4 KiB
Plaintext
|
Advent of Code
|
|||
|
|
|
|||
|
|
br0xen 40*
|
|||
|
|
|
|||
|
|
• [About]
|
|||
|
|
• [Stats]
|
|||
|
|
• [Leaderboard]
|
|||
|
|
• [Settings]
|
|||
|
|
• [Log out]
|
|||
|
|
|
|||
|
|
--- Day 4: The Ideal Stocking Stuffer ---
|
|||
|
|
|
|||
|
|
Santa needs help mining some AdventCoins (very similar to bitcoins) to use as gifts for all the
|
|||
|
|
economically forward-thinking little girls and boys.
|
|||
|
|
|
|||
|
|
To do this, he needs to find MD5 hashes which, in hexadecimal, start with at least five zeroes.
|
|||
|
|
The input to the MD5 hash is some secret key (your puzzle input, given below) followed by a
|
|||
|
|
number in decimal. To mine AdventCoins, you must find Santa the lowest positive number (no
|
|||
|
|
leading zeroes: 1, 2, 3, ...) that produces such a hash.
|
|||
|
|
|
|||
|
|
For example:
|
|||
|
|
|
|||
|
|
• If your secret key is abcdef, the answer is 609043, because the MD5 hash of abcdef609043
|
|||
|
|
starts with five zeroes (000001dbbfa...), and it is the lowest such number to do so.
|
|||
|
|
• If your secret key is pqrstuv, the lowest number it combines with to make an MD5 hash
|
|||
|
|
starting with five zeroes is 1048970; that is, the MD5 hash of pqrstuv1048970 looks like
|
|||
|
|
000006136ef....
|
|||
|
|
|
|||
|
|
Your puzzle answer was 282749.
|
|||
|
|
|
|||
|
|
--- Part Two ---
|
|||
|
|
|
|||
|
|
Now find one that starts with six zeroes.
|
|||
|
|
|
|||
|
|
Your puzzle answer was 9962624.
|
|||
|
|
|
|||
|
|
Both parts of this puzzle are complete! They provide two gold stars: **
|
|||
|
|
|
|||
|
|
At this point, you should return to your advent calendar and try another puzzle.
|
|||
|
|
|
|||
|
|
Your puzzle input was yzbqklnj.
|
|||
|
|
|
|||
|
|
You can also [Shareon Twitter Google+ Reddit] this puzzle.
|
|||
|
|
|
|||
|
|
References
|
|||
|
|
|
|||
|
|
Visible links
|
|||
|
|
. http://adventofcode.com/
|
|||
|
|
. http://adventofcode.com/about
|
|||
|
|
. http://adventofcode.com/stats
|
|||
|
|
. http://adventofcode.com/leaderboard
|
|||
|
|
. http://adventofcode.com/settings
|
|||
|
|
. http://adventofcode.com/auth/logout
|
|||
|
|
. https://en.wikipedia.org/wiki/Bitcoin#Mining
|
|||
|
|
. https://en.wikipedia.org/wiki/Bitcoin
|
|||
|
|
. https://en.wikipedia.org/wiki/MD5
|
|||
|
|
. https://en.wikipedia.org/wiki/Hexadecimal
|
|||
|
|
. http://adventofcode.com/
|
|||
|
|
. https://twitter.com/intent/tweet?text=I%27ve+completed+%22The+Ideal+Stocking+Stuffer%22+%2D+Day+4+%2D+Advent+of+Code&url=http%3A%2F%2Fadventofcode%2Ecom%2Fday%2F4&related=ericwastl&hashtags=AdventOfCode
|
|||
|
|
. https://plus.google.com/share?url=http%3A%2F%2Fadventofcode%2Ecom%2Fday%2F4
|
|||
|
|
. http://www.reddit.com/submit?url=http%3A%2F%2Fadventofcode%2Ecom%2Fday%2F4&title=I%27ve+completed+%22The+Ideal+Stocking+Stuffer%22+%2D+Day+4+%2D+Advent+of+Code
|