Nested Case

program nested_case;
uses crt;
label lagi;
var
kd,kd_kls,lg :char;
nm_ps,nm_ksr,napem,nm_kls :string;
hrg,total,ppn,tobay,jumbel,ubay,ukem :real;
begin
lagi:
clrscr;
writeln(' AGEN PESAWAT TERBANG "QUICK AIR"');
WRITELN(' PENJUALAN TIKET PESAWAT');
WRITELN('------------------------------------------------------------------------');

writeln;
write('Masukkan Nama Kasir: ');readln(nm_ksr);
write('Masukkan Nama Pemesan: ');readln(napem);
write('Masukkan Kode Pesawat [L/G/A]: ');readln(kd);
write('Masukkan Kelas Pesawat [1/2]: ');readln(kd_kls);
write('Masukkan Jumlah Beli: ');readln(jumbel);
case kd of
'L','l':begin
nm_ps:='Lion Air';
case kd_kls of
'1':begin
nm_kls:='VIP';
hrg:=8000000;
end;
'2':begin
nm_kls:='Executive';
hrg:=6000000;
end;
end;
end;
'G','g':begin
nm_ps:='Garuda Indonesia';
case kd_kls of
'1':begin
nm_kls:='VIP';
hrg:=8500000;
end;
'2':begin
nm_kls:='Executive';
hrg:=6500000;
end;
end;
end;
'A','a':begin
nm_ps:='Adam Air';
case kd_kls of
'1':begin
nm_kls:='VIP';
hrg:=7000000;
end;
'2':begin
nm_kls:='Executive';
hrg:=4000000;
end;
end;
end;
end;
total:=hrg*jumbel;
ppn:=0.1*total;
tobay:=total+ppn;
clrscr;
writeln(' AGEN PESAWAT TERBANG "QUICK AIR"');
WRITELN(' PENJUALAN TIKET PESAWAT');
WRITELN('----------------------------------------------------------------');
writeln;
writeln('Nama Kasir : ',nm_ksr);
writeln('Nama Pemesan : ',napem);
writeln;
writeln(' Rincian Pemesanan Tiket');
WRITELN('---------------------------------------------------------------');
writeln('Kode Pesawat : ',kd);
writeln('Nama Pesawat : ',nm_ps);
writeln('Harga Tiket :Rp. ',hrg:0:0);
writeln('Kelas yang Dipesan: ',nm_kls);
writeln('Jumlah Beli : ',jumbel:0:0);
writeln('Total : ',total:0:0);
WRITELN('-------------------------------------------------------------');
writeln('PPN 10% : ',ppn:0:0);
writeln('Total Bayar : ',tobay:0:0);
WRITELN('------------------------------------------------------------');
write('Uang Bayar : ');readln(ubay);
ukem:=ubay-tobay;
writeln('Uang Kembali : ',ukem:0:0);
write('Ingin Input lagi (Y/N)? ');read(lg);
case lg of
'Y','y':goto lagi;
end;
readln;
end.