33 lines
565 B
Perl
33 lines
565 B
Perl
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package Day2::Part1;
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use 5.36.0;
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use List::Util qw/ sum pairmap /;
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use List::MoreUtils qw/ part zip /;
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sub read_file(@lines) {
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return map { [split] } @lines;
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}
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sub is_safe(@report) {
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my $asc = $report[1] - $report[0];
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my $level = shift @report;
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while(@report) {
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my $next = shift @report;
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my $delta = $next - $level;
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return 0 unless $delta*$asc >= 0;
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return 0 unless 1 <= abs($delta) <= 3;
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$level = $next;
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}
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return 1;
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}
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sub solve(@reports) {
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return sum map { is_safe(@$_) } @reports;
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}
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1;
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