Assumes lines are always paired after the header line: 

use strict;
use warnings;

print scalar <STDIN>;
while (<STDIN>) {
    chomp;
    print $_, scalar <STDIN>;
}

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Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
"Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."

In reply to Re: When every 2 lines of a file (sans first) should be 1... by BrowserUk
in thread When every 2 lines of a file (sans first) should be 1... by metaperl

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