$string = "KHI0339B__P_H_Vita_Korangi_Ind_A";
my $string_1 = "HGW6120A__S_Popalzai_Cross_A";
$string_1 =~ s/__[a-zA-Z]{1,2}_/__/g;

print ":$string_1:\n";

Output :-
:HGW6120A__gPopalzai_Cross_A:

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those input I get it from a huge input file. I have only those 2 pattern types. what is the modification required to handle those both types ?

In reply to question : regex by greatshots

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