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