Difficult postcodes are as below

Whose first three characters are out of these
AB5, ZE1, ZE2, ZE3, G84, IV1, IV2, IV3, IV4, IV5, IV6, IV7, IV8, IV9, KW1, KW2, KW3, KW4, KW5, KW6, KW7, KW8, KW9, HS1, HS2, HS3, HS4, HS5, HS6, HS7, HS8, HS9, BT1, BT2, BT3, BT4, BT5, BT6, BT7, BT8, BT9, IM1, IM2, IM3, IM4, IM5, IM6, IM7, IM8, IM9, GY1, GY2, GY3, GY4, GY5, GY6, GY7, GY8, GY9, JE1, JE2, JE3, JE4, JE5, JE6, JE7, JE8, JE9

Whose first four characters are out of these
AB31, AB33, AB35, AB36, AB37, AB38, AB44, AB45, AB51, AB52, AB53, AB54, AB55, AB56, KA27, KA28, BT10, BT11, BT12, BT13, BT14, BT15, BT16, BT17, BT18, BT19, BT20, BT21, BT22, BT23, BT24, BT25, BT26, BT27, BT28, BT29, BT30, BT31, BT32, BT33, BT34, BT35, BT36, BT37, BT38, BT39, BT40, BT41, BT42, BT43, BT44, BT45, BT46, BT47, BT48, BT49, BT50, BT51, BT52, BT53, BT54, BT55, BT56, BT57, BT58, BT59, BT60, BT61, BT62, BT63, BT64, BT65, BT66, BT67, BT68, BT69, BT70, BT71, BT72, BT73, BT74, BT75, BT76, BT77, BT78, BT79, BT80, BT81, BT82, BT83, BT84, BT85, BT86, BT87, BT88, BT89, BT90, BT91, BT92, BT93, BT94, GY10, GY11, GY12, GY13, GY14, GY15, GY16, GY17, GY18, GY19, GY20, JE10, JE11, JE12, JE13, JE14, JE15, JE16, JE17, JE18, JE19, JE20, PH19, PH20, PH21, PH22, PH25, PH26, PH30, PH31, PH32, PH33, PH34, PH35, PH36, PH37, PH38, PH39, PH40, PH41, PH49, PH50, FK18, FK19, FK20, FK21, IV10, IV11, IV12, IV13, IV14, IV15, IV16, IV17, IV18, IV19, IV20, IV21, IV22, IV23, IV24, IV25, IV26, IV27, IV28, IV29, IV30, IV31, IV32, IV33, IV34, IV35, IV36, IV37, IV38, IV39, IV40, IV41, IV42, IV43, IV44, IV45, IV46, IV47, IV48, IV49, IV50, IV51, IV52, IV53, IV54, IV55, IV56, IV57, IV58, IV59, IV60, IV61, IV62, IV63, KW10, KW11, KW12, KW13, KW14, KW15, KW16, KW17, PA20, PA21, PA22, PA23, PA24, PA25, PA26, PA27, PA28, PA29, PA30, PA31, PA32, PA33, PA34, PA35, PA36, PA37, PA38, PA39, PA40, PA41, PA42, PA43, PA44, PA45, PA46, PA47, PA48, PA49, PA50, PA51, PA52, PA53, PA54, PA55, PA56, PA57, PA58, PA59, PA60, PA61, PA62, PA63, PA64, PA65, PA66, PA67, PA68, PA69, PA70, PA71, PA72, PA73, PA74, PA75, PA76, PA77, PA78, PA79, PA80, PA81, PA82, PA83, PA84, PA85, PA86, PA87, PA88, P040, P030, P031, P032, P033, P034, P035, P036, P037, P038

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