75 lines
2.5 KiB
Plaintext
75 lines
2.5 KiB
Plaintext
Advent of Code
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--- Day 6: Signals and Noise ---
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Something is jamming your communications with Santa. Fortunately, your
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signal is only partially jammed, and protocol in situations like this is to
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switch to a simple repetition code to get the message through.
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In this model, the same message is sent repeatedly. You've recorded the
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repeating message signal (your puzzle input), but the data seems quite
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corrupted - almost too badly to recover. Almost.
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All you need to do is figure out which character is most frequent for each
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position. For example, suppose you had recorded the following messages:
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eedadn
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drvtee
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eandsr
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raavrd
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atevrs
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tsrnev
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sdttsa
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rasrtv
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nssdts
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ntnada
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svetve
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tesnvt
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vntsnd
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vrdear
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dvrsen
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enarar
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The most common character in the first column is e; in the second, a; in the
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third, s, and so on. Combining these characters returns the error-corrected
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message, easter.
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Given the recording in your puzzle input, what is the error-corrected
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version of the message being sent?
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Your puzzle answer was cyxeoccr.
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--- Part Two ---
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Of course, that would be the message - if you hadn't agreed to use a modified repetition code instead.
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In this modified code, the sender instead transmits what looks like random data, but for each character, the character they actually want to send is
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slightly less likely than the others. Even after signal-jamming noise, you can look at the letter distributions in each column and choose the least common
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letter to reconstruct the original message.
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In the above example, the least common character in the first column is a; in the second, d, and so on. Repeating this process for the remaining characters
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produces the original message, advent.
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Given the recording in your puzzle input and this new decoding methodology, what is the original message that Santa is trying to send?
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Your puzzle answer was batwpask.
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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/2016/about
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. http://adventofcode.com/2016/support
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. http://adventofcode.com/2016/events
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. http://adventofcode.com/2016/settings
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. http://adventofcode.com/2016/auth/logout
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. http://adventofcode.com/2016
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. http://adventofcode.com/2016
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. http://adventofcode.com/2016/leaderboard
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. http://adventofcode.com/2016/stats
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. http://adventofcode.com/2016/sponsors
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. http://adventofcode.com/2016/sponsors
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. https://en.wikipedia.org/wiki/Repetition_code
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. http://adventofcode.com/2016
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. http://adventofcode.com/2016/day/6/input
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