>perl -wMstrict -le
"my $s = '79899920179';
 ;;
 my @n = $s =~ m{ \G (\d{2,3}?) (?(?{ $^N < 32 }) (*FAIL)) }xmsg;
 printf qq{'$_' } for @n;
"
'79' '89' '99' '201' '79'