Singapore is like this - 5 digit numeric postal code in a country where most people live in apartment buildings (HDB's). As a result, most towers (blocks) have

Singapore is like this - 5 digit numeric postal code in a country where most people live in apartment buildings (HDB's). As a result, most towers (blocks) have their own post code. Even in complexes with 3 towers sharing a common main level (floors B2 through 3), still have their own postcode. If you go on website and put your postcode, it will autocomplete the address except for the unit number.