AoC 2022, day 8

my @trees = $*IN.lines.map({ .comb».Int.Array }).Array;
my \rows = +@trees;
my \cols = +@trees[0];

put 'part 1: ',
    2 * (rows + cols) - 4 +
    (1..^rows-1 X 1..^cols-1).grep(-> ($r,$c) {
        @trees[$r;$c] > (
            @trees[$r;^$c        ].all |
            @trees[$r;$c^..cols-1].all |
            @trees[^$r;        $c].all |
            @trees[$r^..rows-1;$c].all
    ) });

my method viewing-distance(@A : UInt:D $height --> UInt:D) {
    (@A.first(* ≥ $height, :k) // (+@A - 1)) + 1
}

put 'part 2: ',
    (1..^rows-1 X 1..^cols-1).map(-> ($r,$c) {
        [*] (@trees[$r;$c^...0],
             @trees[$r;$c^..cols-1],
             @trees[$r^...0;$c],
             @trees[$r^..rows-1;$c]
            ).map({ .&viewing-distance(@trees[$r;$c]) })
    }).max;