anchor.diff:  HOLYHEAD,1407
   GOLSPIE,1408
   HOLSWORTHY,1409
  +GLASGOW,141
   ALTON,1420
   HALIFAX,1422
  +BOROUGHBRIDGE,14233
  +BOROUGHBRIDGE,14234
  +BOROUGHBRIDGE,14239
  +HARROGATE,14232
  +HARROGATE,14235
  +HARROGATE,14236
  +HARROGATE,14237
  +HARROGATE,14238
   HASTINGS,1424
   RINGWOOD,1425
   GAINSBOROUGH,1427
   HASLEMERE,1428
   HARTLEPOOL,1429
  +MARKET WEIGHTON,14306
  +MARKET WEIGHTON,14307
  +MARKET WEIGHTON,14308
  +MARKET WEIGHTON,14309
  +NORTH CAVE,14302
  +NORTH CAVE,14303
  +NORTH CAVE,14304
  +NORTH CAVE,14305
   HELMSDALE,1431
   HEREFORD,1432
   HATHERSAGE,1433
  +BELLINGHAM,14342
  +BELLINGHAM,14344
  +BELLINGHAM,14349
  +HALTWHISTLE,14343
  +HALTWHISTLE,14345
  +HEXHAM,14346
  +HEXHAM,14347
  +HEXHAM,14348
   HEATHFIELD,1435
   HELENSBURGH,1436
  +CLYNDERWEN,14372
  +CLYNDERWEN,14373
  +CLYNDERWEN,14374
  +CLYNDERWEN,14375
  +HAVERFORDWEST,14376
  +HAVERFORDWEST,14377
  +HAVERFORDWEST,14378
  +HAVERFORDWEST,14379
  +CLYNDERWEN,1437
  +CLYNDERWEN,1437
  +CLYNDERWEN,1437
  +CLYNDERWEN,1437
   STEVENAGE,1438
   HELMSLEY,1439
   HAVERHILL,1440
  
positive.code: FORFAR,1307
  BRIDPORT,1308
  FORRES,1309
  FORT AUGUSTUS,1320
  DARTFORD,1322
  EASTBOURNE,1323
  
negative.code: ST,1994
  GARSTANG,1995
  STRATHPEFFER,1997
  LONDON,20
  SOUTHAMPTON,238
  PORTSMOUTH,239
  COVENTRY,24
  BALLYCASTLE,2820
  MARTINSTOWN,2821
  BALLYMENA,2825
  