It's been a long time since I've coded. I've never looked into scripts for google spreadsheets before. I just want to make a simple effect to edit the spreadsheet. If I understand correctly, this is doable so long as you run it manually?
The syntax is throwing me off too much. My basic goal is to set each cell in a fixed column range to equal itself plus the value in the adjacent column, and then set that second value to 0.
My instinct would be to do something such as
CellRange[i][j] selected = C9:D13;
for(i=0,i<selectedrange.length,i++){
SpreadsheetApp.getActiveRange().setValue(selected[i][j]+selected[i][j+1];
SpreadsheetApp.getRange(selected[i][j+1]).setValue(0);
}
That's probably terribly wrong but I feel I ought to at least throw my best guess out before asking for help.