@ranges = ([172,178],[183,189],[201,208]);

##</code><code>##

$input =~ s/(\d+)/(grep {$1 >= $_->[0] && $1 <= $_->[1]} @ranges) ? $symbol : $1/eg;

##</code><code>##

@ranges = ();
push @ranges, "[172,178]";
push @ranges, "[183,189]";
push @ranges, "[201,208]";