Brian Buller
bb174c5f5b
Removed solutions from 'problem' files Added 'helpers' file with functions that I commonly use in these solutions.
92 lines
3.7 KiB
Plaintext
92 lines
3.7 KiB
Plaintext
Advent of Code
|
||
|
||
--- Day 2: Bathroom Security ---
|
||
|
||
You arrive at Easter Bunny Headquarters under cover of darkness. However, you left in such a rush that you forgot to
|
||
use the bathroom! Fancy office buildings like this one usually have keypad locks on their bathrooms, so you search the
|
||
front desk for the code.
|
||
|
||
"In order to improve security," the document you find says, "bathroom codes will no longer be written down. Instead,
|
||
please memorize and follow the procedure below to access the bathrooms."
|
||
|
||
The document goes on to explain that each button to be pressed can be found by starting on the previous button and
|
||
moving to adjacent buttons on the keypad: U moves up, D moves down, L moves left, and R moves right. Each line of
|
||
instructions corresponds to one button, starting at the previous button (or, for the first line, the "5" button); press
|
||
whatever button you're on at the end of each line. If a move doesn't lead to a button, ignore it.
|
||
|
||
You can't hold it much longer, so you decide to figure out the code as you walk to the bathroom. You picture a keypad
|
||
like this:
|
||
|
||
1 2 3
|
||
4 5 6
|
||
7 8 9
|
||
|
||
Suppose your instructions are:
|
||
|
||
ULL
|
||
RRDDD
|
||
LURDL
|
||
UUUUD
|
||
|
||
• You start at "5" and move up (to "2"), left (to "1"), and left (you can't, and stay on "1"), so the first button is
|
||
1.
|
||
• Starting from the previous button ("1"), you move right twice (to "3") and then down three times (stopping at "9"
|
||
after two moves and ignoring the third), ending up with 9.
|
||
• Continuing from "9", you move left, up, right, down, and left, ending with 8.
|
||
• Finally, you move up four times (stopping at "2"), then down once, ending with 5.
|
||
|
||
So, in this example, the bathroom code is 1985.
|
||
|
||
Your puzzle input is the instructions from the document you found at the front desk. What is the bathroom code?
|
||
|
||
Your puzzle answer was ______.
|
||
|
||
--- Part Two ---
|
||
|
||
You finally arrive at the bathroom (it's a several minute walk from the lobby so visitors can behold the many fancy
|
||
conference rooms and water coolers on this floor) and go to punch in the code. Much to your bladder's dismay, the
|
||
keypad is not at all like you imagined it. Instead, you are confronted with the result of hundreds of man-hours of
|
||
bathroom-keypad-design meetings:
|
||
|
||
1
|
||
2 3 4
|
||
5 6 7 8 9
|
||
A B C
|
||
D
|
||
|
||
You still start at "5" and stop when you're at an edge, but given the same instructions as above, the outcome is very
|
||
different:
|
||
|
||
• You start at "5" and don't move at all (up and left are both edges), ending at 5.
|
||
• Continuing from "5", you move right twice and down three times (through "6", "7", "B", "D", "D"), ending at D.
|
||
• Then, from "D", you move five more times (through "D", "B", "C", "C", "B"), ending at B.
|
||
• Finally, after five more moves, you end at 3.
|
||
|
||
So, given the actual keypad layout, the code would be 5DB3.
|
||
|
||
Using the same instructions in your puzzle input, what is the correct bathroom code?
|
||
|
||
Your puzzle answer was _____.
|
||
|
||
Both parts of this puzzle are complete! They provide two gold stars: **
|
||
|
||
If you still want to see it, you can get your puzzle input.
|
||
|
||
References
|
||
|
||
Visible links
|
||
. http://adventofcode.com/
|
||
. http://adventofcode.com/2016/about
|
||
. http://adventofcode.com/2016/support
|
||
. http://adventofcode.com/2016/events
|
||
. http://adventofcode.com/2016/settings
|
||
. http://adventofcode.com/2016/auth/logout
|
||
. http://adventofcode.com/2016
|
||
. http://adventofcode.com/2016
|
||
. http://adventofcode.com/2016/leaderboard
|
||
. http://adventofcode.com/2016/stats
|
||
. http://adventofcode.com/2016/sponsors
|
||
. http://adventofcode.com/2016/sponsors
|
||
. http://adventofcode.com/2016
|
||
. http://adventofcode.com/2016/day/2/input
|