Add column

gistfile1.js

function test(){
  
  var info = {};
  info["value"] =-1;
  info["range"] = SpreadsheetApp.getActiveSheet().getRange(3,4);
  info["source"] = SpreadsheetApp.getActiveSpreadsheet();

  doEdit(info);
}


function doEdit(eventInfo) {

  var sheet = SpreadsheetApp.getActiveSpreadsheet();
  
  var stockInfo = Number(eventInfo.value);
  var editRange = eventInfo.range;
  var col = editRange.getColumn();
  var sheetId = sheet.getActiveSheet().getIndex();
  
  if( isNaN(stockInfo) && stockInfo !== '' ){
    if(sheet)
      sheet.toast("You have enetered something that isn't a number", "Warning", 3);
    return;
  }
  
  if(editRange.getWidth() != 1 || editRange.getHeight() != 1){
    return;
  }
  
  if(editRange.getRow() < 2){
    return;
  }

  //A=1, B=2, C=3, D=4, E=5, F=6, G=7, H=8, I=9, J=10, K=11
  if(
    //
    // EDIT BELOW
    (sheetId == 1 && (col == 4))
    || (sheetId == 2 && (col == 4 || col == 6))
  
    // STOP EDITING
    //
  ){
      
    var originalCell = editRange.offset(0,-1);
    var original = Number(originalCell.getValue());
    var add = Number(eventInfo.value);
    originalCell.setValue(original+add);

    editRange.setValue('');

  }
  return false;
}