to collect the total amount s of related same field

hi Guru's,

i had a requriment that to collect the totals of similar customers accounts and

profit center.

let me explain in detail i had a requriment that in an internal table i have account number, customer, profit centre and amounts in this case i have to sum all the amounts of similar account customer and profit centre and pass it to an internal table.

please help me i am struck in this i have used at end of but it does n't meet my requriment.

thanks in advance