two parameters to one table

Hai...
I am working Crystal Report 8.5 for report designing... to my VBProject... There i require a report... which is having the interface with the below listed components.
start date, end date are two date values.. should be passed as parameters... to the required report...
the report should be generated from.. LEDGER table. It consists of account code, date, amount, drcr. they represent.... account code of the account, the date of transaction , amount of transaction and the transaction type whether it is 'D'(debit) or 'C'(credit).

What i want to ask you is .... i pass two parameters from front end... namely... start date, end date. i want to have the Opening balance of each account as two fields.. namely... debit, and credit... It should be difference of sum of debits and sum of credits... what ever is more difference should be kept in the corresponding column....

similarly... the transaction amount of each account should be calculated... they should be the sum of debits and the sum of credits... only... they should be kept individually...

the output should be as follows ...

AccountCode`````OpeningBalance```````Transaction
-----------------------------------------------------------------------------------
.........................debit..........credit...............debit..........credit..........
==============================================

101 ----------------2000--------0--------------3000------------4000-----
102---------------------0-------2500-----------5000------------1500-----
103--------------------0----------0-------------2000-------------4000-----


thanks in advance...