$margin = 10;
printf "'%${margin}s'\n", 'x';

__output__

'         x'
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You don't need references to $_ in the foreach or split lines. The whole point about the default variable is that you can leave out the variable, and focus on the operation. Fewer implementation details, more result.

In related news,.... since you don't need $a or $b, just tell Perl to discard them by taking a slice of the split result:

... (split( /\t/ ))[2,3];
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But you only need $c & $d for two lines, to join back together. So why not merge the two lines:

... join '/', (split( /\t/ ))[2,3];
[download]

You only use $qq to add the result of the join into @qqq, so save another line:

push @qqq,  join '/', (split( /\t/ ))[2,3];
[download]

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