Unrelated comments:

• Declaring all the variables at the start is needed in Pascal, not Perl. Use the smallest possible scope.
• No need to call ls:

  @tpr = `ls *.tpr`;
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  could be written in a more Perlish way as

  @tpr = glob '*.tpr';
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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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