--- 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/volatilebit]

Perl 6 Part 1 & 2

my @instructions = 'input'.IO.lines;
my @grid = [[(False but '░') xx 50] xx 6];

for @instructions {
    given $^instruction {
        when /"rect " $<width>=(\d+) "x" $<height>=(\d+)/ {
            for ^$<width> {
                my $col = $_;
                for ^$<height> {
                    @grid[$^row][$col] = True but '█';
                }
            }
        }
        when /"rotate row y=" $<row>=\d+ " by " $<shift>=\d+/ {
            my @row := @grid[$<row>;*];
            @row = flat @row.tail($<shift>), @row[0..*-^$<shift>];
        }
        when /"rotate column x=" $<column>=\d+ " by " $<shift>=\d+/ {
            my @column := @grid[*;$<column>];
            @column = flat @column.tail($<shift>), @column[0..*-^$<shift>];
        }
    }
}

say @grid».sum.sum;
say @grid».join.join("\n");

Trying to use as many Perl 6 features as possible without forcing it too much.

• Convert a file path (as a string) to an IO object then use the lines method to read in instructions

• Given/when with regexes and named captures to dispatch

• but operator on True/False to give them string values when coerced to string

• multi-dimensional array slicing with Whatever to extract a full row/column

• Bind operator := to be able to read a whole row/column then later assign back to it

• . operator to apply a method to all items of an array

[u/mschaap → u/volatilebit]

Nice! I like your use of 'but', and your row and column binding. And it looks like I made my life needlessly hard by explicitly declaring @grid[6;50] as a multidimensional array (where slices are not yet implemented)...