use strict;
use warnings;

my @strings = qw(
  foobarbaz111222333444
  barbazfoo111555666999
  bazfoobar999888777666
);

my $text = <<'END';
bdfjadslfjhasdjklfhjklashdflkjadshfjkladhfjkldhfljkafjadfdji
adlfjhdlsjkfuiowerfhwehrbeblbflasdfbhjkaldhqpqheuihfbdfkhyyy
qjdpdbnfdbjdfklbasjfbajksdbfjaksdbfjaksdfbjkasdfhydsfadfjyyy
END

$text x= 1_000_000;
$text .= "bazfoobar999888777666\n";

printf "text size: %d bytes (%.2f mb)\n",
  length($text), length($text) / ( 1024 * 1024 );

my $regex = join '|', map quotemeta, @strings;
$regex = qr/^($regex)$/m;

printf "found %s at %d\n", $1, $-[0] if $text =~ $regex;