sounds like a great candidate for recursion:

getPhoneNumbers(7);

sub getPhoneNumbers {
    my $maxLength = shift;
    my $curPhoneNumber = shift || '0';
    
    if($maxLength - 1) {
        for(my $i = 0; $i < 10; $i++) {
            getPhoneNumbers($maxLength - 1, $curPhoneNumber.$i);
        }
    } else {
        print $curPhoneNumber, "\n";
    }
}

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In reply to Re: Telephone - Nested Loops by ozone
in thread Telephone - Nested Loops by FFRANK

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