I would do this :

my $i;
while (<DATA) {
    print if ($i++ % 2);
}

__DATA__
435
435
f,sdlf,dsl
f,sdlf,dsl
64{#
64{#
Blah
Blah

[download]
or, for a one liner :
perl -i -ne 'print if ($i++ % 2)' filename

[download]

Here $i % 2 is a mean to know if $i is even or not.
HTH

--
zejames

In reply to Re: Even and uneven numbers as RegEx by zejames
in thread Even and uneven numbers as RegEx by New Novice

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