There should be a "g" at the end of those lines: 

my @find = $line[$i] =~ /(?:\A|\t)(abc\d+)(?=\t|\z)/g;

[download]
otherwise the regexp matches only once instead of searching for all abc<some_number>.

And if you happen to need to count each of the abc<some_number> separately you can either process the @find: 

my @find = $line[$i] =~ /(?:\A|\t)(abc\d+)(?=\t|\z)/
my %count;
$count{$_}++ for @find;

[download]

or skip building the array

while ($line[i] =~ /(?:\A|\t)(abc\d+)(?=\t|\z)/g) {
    $count{$1}++;
}

[download]

Jenda
Enoch was right!
Enjoy the last years of Rome.

In reply to Re^2: problem with regex by Jenda
in thread problem with regex by Anonymous Monk

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