if ($line =~ /^0.{9}(\t\d{1,20}){49}/)  {
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Will do the same as your lengthy regex, except, that it doesn't grep all the individual numbers.

OTOH our REs won't match the line at all. I think, this one will serve the purpose better

if (/^0[0-9a-fA-F]{9}(?:\t[\d\.]{1,20}){49}/ {
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Okay: This will also match (e.g.) IP Adresses, as i doesn't take into account, that a number may only contain 1 decimal point, but maybe it's okay. You're the only one who can tell.