how to get row numbers with particualr value from a google spreadsheet in app scrip without using loop? : I am new to spreadsheet scripting. I am generating a report (new sheet) based on another sheet where I enter values daily. In App script i first generate the sheet then I loop through the data range i retrieve from that input sheet.
after that I have merge values based on dates and categories. 
Now my report format is such that rows are categories and dates are columns.
So if in input if there is another value with same date and same category i have to add the value.

My problem is how to check if the value with same date and category exists and already filled in the report.  and I DO NOT want to use loops as I am already in loops so that will make the process run very very slow .