P:\test>perl -wl my $a = 'a' x 10; my $b; $b .= substr( $a, $_, 10-$_ ) . '-' x $_ for 0 .. 9; print $b; ^Z aaaaaaaaaaaaaaaaaaa-aaaaaaaa--aaaaaaa---aaaaaa----aaaaa-----aaaa------aaa-------aa--------a---------