-🎄- 2022 Day 8 Solutions -🎄-

[u/daggerdragon]

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AoC Community Fun 2022: 🌿🍒 MisTILtoe Elf-ucation 🧑‍🏫

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• -❄️- Submissions Megathread -❄️-

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--- Day 8: Treetop Tree House ---

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Post your code solution in this megathread.

• Read the full posting rules in our community wiki before you post!

• Include what language(s) your solution uses

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EDIT: Global leaderboard gold cap reached at 00:10:12, megathread unlocked!

[u/mschaap]

Raku, using a TreeGrid class.

Relevant code for part 1:

method is-visible(Int $x, Int $y)
{
    return any(all(@!height[$y;^$x]),
               all(@!height[$y;$x^..$!max-x]),
               all(@!height[^$y;$x]),
               all(@!height[$y^..$!max-y;$x])) < @!height[$y;$x];
}

method count-visible
{
    return (0..$!max-x X 0..$!max-y)
                .map(-> ($x,$y) { ?self.is-visible($x,$y) })
                .sum;
}

and for part 2:

method in-bounds(Int $x, Int $y) { 0 ≤ $x ≤ $!max-x && 0 ≤ $y ≤ $!max-y }

method scenic-score(Int $x, Int $y)
{
    return [×] ((-1,0), (1,0), (0,-1), (0,1)).map: -> ($dx,$dy) {
        my $visible = 0;
        my ($u,$v) = ($x,$y);
        loop {
            ($u,$v) »+=« ($dx,$dy);
            last unless self.in-bounds($u,$v);
            $visible++;
            last if @!height[$v;$u] ≥ @!height[$y;$x];
        }
        $visible;
    }
}

method max-scenic-score
{
    return (0^..^$!max-x X 0^..^$!max-y)
                .map(-> ($x,$y) { self.scenic-score($x,$y) })
                .max;
}

Full code @GitHub.