c:\@Work\Perl\monks>perl -wMstrict -le
"my $s = '01';
 ;;
 for (0 .. 105) {
   print qq{'$s'};
   $s++;
   $s = '01' if do { (my $t = $s) > 99 };
   }
"
'01'
'02'
'03'
'04'
'05'
'06'
...
'97'
'98'
'99'
'01'
'02'
'03'
'04'
'05'
'06'
'07'