function highliteZeroOrBlank(sheetName,rangeInA1Notation) {
var ss=SpreadsheetApp.getActive();
var sheetName=sheetName||ss.getActiveSheet().getName();
var rangeInA1Notation=rangeInA1Notation||ss.getActiveRange().getA1Notation();
var sh=ss.getSheetByName(sheetName);
var rg=sh.getRange(rangeInA1Notation);
var v=rg.getValues();
var row=rg.getRow();
var col=rg.getColumn();
v.forEach(function(r,i){r.forEach(function(c,j){if(c==0||c==''){sh.getRange(row+i,col+j).setBackground('#ffff00');}});});
}