46 lines
819 B
Perl
46 lines
819 B
Perl
use 5.38.0;
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package Part1;
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use List::AllUtils qw/ /;
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sub parse_input ($input) {
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my ( $directions, undef, @nodes ) = split "\n", $input;
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$directions = [ split "", $directions =~ s/R/1/gr =~ s/L/0/gr ];
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my %nodes;
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for (@nodes) {
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my @n = /([A-Z]+)/g;
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$nodes{ shift @n } = \@n;
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}
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return {
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directions => $directions,
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nodes => \%nodes
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};
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}
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sub solution_1 ($input) {
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my $p = parse_input($input);
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my @directions = $p->{directions}->@*;
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my %nodes = $p->{nodes}->%*;
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my $visited = 0;
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my $next_index = 0;
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my $current = 'AAA';
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while ( $current ne 'ZZZ' ) {
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$visited++;
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$current =
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$nodes{$current}->[ $directions[ $next_index++ % @directions ] ];
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}
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return $visited;
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}
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1;
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