Sybase Philippines

hi to all programmers out there,
please help me with this simple looping program problem.

the following set of rows that has duplicate values of account codes and sub codes are given. (assuming the first set of data are retrieved from a datawindow) the objective is to delete those values that have duplicate rows. the output must have unique values only given data that has duplicate account codes and sub codes: grouping on datawindow will not be allowed.
Account Code Sub Code
1200 KET01
1209 KET01
1202 FLU01
1200 KET01
1209 MPG01
1200 KET01
1200 SNO01
1114 888
1114 888
1114 888
2000 MLD
2000 MLD
2000 MLD
2000 MLD

From the rows given above, the output must be unique values of
account codes and sub codes: the deletion must be made from bottom to top.
1200 KET01
1209 KET01
1202 FLU01
1209 MPG01
1200 SNO01
1114 888
2000 MLD

these is my approach but there seems to be a problem with this:
from the above example, l_row = 14
///////
FOR l_ctr = l_row TO 1 STEP - 1
l_minus = l_row - 1
IF l_minus > 1 THEN
s_acct_code = uo_gl.dw_dtl.GetItemString(l_minus ,'acct_code')
s_sys_acct_code = uo_gl.dw_dtl.GetItemString(l_minus,'sys_acct_code')
s_sub_code = uo_gl.dw_dtl.GetItemString(l_minus,'sub_code')

s_sys_acct_code2 = uo_gl.dw_dtl.GetItemString(l_ctr,'sys_acct_code')
s_acct_code2 = uo_gl.dw_dtl.GetItemString(l_ctr,'acct_code')
s_sub_code2 = uo_gl.dw_dtl.GetItemString(l_ctr,'sub_code')

IF s_sys_acct_code = s_sys_acct_code2 AND s_acct_code = s_acct_code2 AND s_sub_code = s_sub_code2 THEN
uo_gl.dw_dtl.deleterow(l_ctr)
ELSE
l_minus2 = l_minus - 1
FOR l_ctm = l_row3 TO 1 STEP -1
l_ctr4 = l_ctr + 1

s_sys_acct_code2 = uo_gl.dw_dtl.GetItemString(l_ctr4,'sys_acct_code')
s_acct_code2 = uo_gl.dw_dtl.GetItemString(l_ctr4,'acct_code')
s_sub_code2 = uo_gl.dw_dtl.GetItemString(l_ctr4,'sub_code')

s_sys_acct_code3 = uo_gl.dw_dtl.GetItemString(l_ctm,'sys_acct_code')
s_acct_code3 = uo_gl.dw_dtl.GetItemString(l_ctm,'acct_code')
s_sub_code3 = uo_gl.dw_dtl.GetItemString(l_ctm,'sub_code')

IF s_sys_acct_code3 = s_sys_acct_code2 AND s_acct_code3 = s_acct_code2 AND s_sub_code3 = s_sub_code2 THEN
uo_gl.dw_dtl.deleterow(l_ctr)
EXIT
END IF
NEXT
l_row3 = l_row - 1
END IF
END IF
l_row = l_row - 1
NEXT
///////////

thanks in advance. any form of help will be greatly appreciated.