modfiy code

[awadh]

Hi

the code below will remove duplicate lines and sorting .

i would like to modify the code below to add more function

as

1- if g1,g2,g3,g4 =0 then line will be removed like

DDS,20110523,0,0,0,0,24


2-if g1,g2,g3,g4 =g4 of the line before then line will be removed like

the line as
DDS,20110526,1.1,1.1,1.1,1.1,29
DDS,20110525,2.4,2.7,2.3,1.1,22

the txt file contain more then 3000 lines and different q(clo 0)(name as DDS ,RRB,EES...etc) and date (clo 1)


thanks