Google App Script for Sheets

I have data in sheet such as - date, time, symbol, buy/sell, qty, price, etc. i want google app script codes to find first transaction of any day for particular symbol( buy or sell) and give it name and name and later for same symbol on same date - it should add/reduce qty from first transation qty eg. first transaction is sell - it should display qty as "-" and later for same symbol it should add/reduce qty from this and group all such transaction for particular day