28 lines
573 B
Perl
28 lines
573 B
Perl
use lib '.';
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use Part1;
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package Part2;
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use List::AllUtils qw/ sum /;
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use 5.36.0;
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sub valid_equation ( $total, @numbers ) {
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return $numbers[0] == $total if @numbers == 1;
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return 0 if $numbers[0] > $total;
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my $i = shift @numbers;
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my $j = shift @numbers;
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return 1 if valid_equation( $total, "$i$j", @numbers );
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return 1 if valid_equation( $total, $i*$j, @numbers );
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return 1 if valid_equation( $total, $i+$j, @numbers );
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return 0;
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}
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sub solve ($equations) {
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return sum map { $_->[0] } grep { valid_equation(@$_) } @$equations;
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}
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1;
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