my @lines = split /\n/, `cat data.txt`;
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can be replaced by

chomp( my @lines = `cat data.txt` );
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It only makes sense to commands different to cat , of course, otherwise you'd just

open my $IN, '<', 'data.txt' or die $!;
chomp( my @lines = <$IN> );
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($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
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