my $c='aff001';
print $c++, "\n" for 0..5;
__END__
aff001
aff002
aff003
aff004
aff005
aff006

##</code><code>##

my $c='aff998';
print $c++, "\n" for 0..5;
__END__
aff998
aff999
afg000
afg001
afg002
afg003