Pour ceux que ça intéresse, la regex pour les codes postaux des zones difficiles (Chronopost):

^(01410|03250|04110|04120|04130|04140|04150|04160|04170|04230|04240|04250|04260|04280|04300|04310|04320|04330|04340|04360|04370|04400|04420|04510|04530|04600|04700|04800|04850|05110|05120|05130|05150|05160|05170|05190|05200|05220|05240|05250|05260|05290|05300|05310|05320|05330|05340|05350|05400|05460|05470|05480|05500|05560|05600|05700|05800|06140|06260|06340|06380|06390|06420|06430|06440|06450|06460|06470|06530|06540|06620|06660|06670|06690|06710|06750|06790|06830|06850|06910|06950|09110|09140|09220|09230|09300|09310|09390|09400|09460|09800|11140|11160|11190|11240|11250|11260|11270|11300|11310|11330|11340|11350|11360|11500|11570|11580|11600|11620|12360|12380|12470|12480|12490|12600|15150|15200|15300|15380|15400|17111|17123|17190|17310|17370|17410|17480|17550|17580|17590|17630|17650|17670|17740|17840|17880|17940|22870|25120|25140|25160|25190|25240|25370|25380|25450|25470|25650|29242|29253|29259|29980|29990|30570|31110|31350|31440|34260|34330|38112|38114|38119|38134|38142|38190|38250|38350|38520|38580|38650|38680|38710|38740|38750|38770|38830|38860|38880|38930|38970|39150|39200|39220|39250|39260|39310|39400|39460|39520|42660|42920|43150|48100|50170|56360|56590|56780|56840|63113|63150|63240|63610|63650|63660|63680|63840|63850|64130|64430|64440|64470|64490|64560|64570|65110|65120|65170|65200|65240|65260|65370|65410|65440|65510|65560|65590|65710|66120|66150|66210|66220|66230|66260|66290|66320|66340|66360|66480|66500|66730|66760|66800|66820|70440|73110|73120|73130|73140|73150|73170|73210|73250|73260|73270|73300|73310|73320|73340|73350|73370|73390|73400|73440|73450|73460|73480|73500|73530|73550|73570|73590|73610|73620|73630|73640|73660|73670|73700|73710|73720|73730|73870|74110|74120|74170|74190|74220|74260|74300|74310|74340|74360|74390|74400|74420|74430|74440|74450|74470|74480|74490|74550|74560|74660|74740|74920|83630|83840|84390|85330|85350|85630|85680|85740|88160| 88310|88340|88540|88560|90200|98000)$