27 lines
413 B
Perl
27 lines
413 B
Perl
use 5.38.0;
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package Part2;
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use Part1;
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use List::AllUtils qw/ all sum /;
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sub predict(@entries) {
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my $sum = 0;
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until( all { !$_ } @entries ) {
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$sum = $entries[0]-$sum;
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@entries = map { $entries[$_]-$entries[$_-1] } 1..$#entries;
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}
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return -$sum;
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}
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sub solution_2 ($input) {
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my @lines = map { [split]} split "\n", $input;
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return sum map { predict(@$_) } @lines;
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}
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1;
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