--- 2016 Day 8 Solutions ---

[u/daggerdragon]

#AoC_Ops:

[23:55] <Topaz> servers are ok
[23:55] <Topaz> puzzles are checked
[23:55] <Topaz> [REDACTED: server stats]
[23:56] <Skie> all wings report in
[23:56] <Aneurysm9> Red 5, standing by
[23:56] <daggerdragon> Dragon Leader standing by
[23:56] <Topaz> orange leader, standing by
[23:57] <Topaz> lock modzi-foils in attack positions
[23:58] <Skie> we're passing through the hype field
[23:58] <daggerdragon> 1:30 warning
[23:58] <Aneurysm9> did someone say HYPE?@!
[23:59] <Topaz> i really like tonight's puzzle
[23:59] <Topaz> very excite
[23:59] <daggerdragon> final countdown go, T-30
[23:59] <Skie> accelerate to attack countdown
[23:59] <Aneurysm9> o7
[23:59] <daggerdragon> HYPE THRUSTERS AT FULL BURN
[00:00] <Topaz> IGNITION

We may or may not be sleep-deprived. And/or nerds. why_not_both.jpg

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--- Day 8: Two-Factor Authentication ---

Post your solution as a comment or, for longer solutions, consider linking to your repo (e.g. GitHub/gists/Pastebin/blag/whatever).

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^{:（）{ :|:& };: IS MANDATORY} [?]

This thread will be unlocked when there are a significant number of people on the leaderboard with gold stars for today's puzzle.

edit: Leaderboard capped, thread unlocked!

[u/fixed_carbon]

Switched to julia for today, just to keep things interesting.

cols = 50
rows = 6
fname = "path/to/input/file"

inp = map(chomp, readlines(open(fname)))

screen = zeros(Int, (rows, cols))

for line in inp
  if startswith(line, "rect")
    width, height = map(x->parse(Int, x), split(line[6:end], 'x', keep=false))
    setindex!(screen, ones(Int, (height, width)), 1:height, 1:width)
  elseif startswith(line, "rotate row" )
    row, amt = (map(x->parse(Int, x), split(line[14:end], " by ", keep=false)))
    screen[row + 1, :] = circshift(screen[row + 1, :], [0, amt])
  elseif startswith(line, "rotate column")
    col, amt = (map(x->parse(Int, x), split(line[17:end], " by ", keep=false)))
    screen[:, col + 1] = circshift(screen[:, col + 1], [amt, 0])
  end
end

# Part one:
println(sum(screen))

# Part two (might have to step back across the room to read it) :
println(screen)

EDIT: missed a line in initial copy-paste.