function Left(str, n){

                if (n <= 0)

                    return "";

                else if (n > String(str).length)

                    return str;

                else

                    return String(str).substring(0,n);

        }

        function IntNumber(Temp){

                if(Temp.indexOf(".")!="-1")

                        return Left(Temp,Temp.indexOf("."));

                else

                        return Temp;

                

                

        }
		//Set the number of days acording to the difrence between pickup date and return date	
	function Set_DayNum()
	{		
			var iYearGap = 0;
                        var iHouresGap = 0;
			
			
			var dPickDate = new Date(document.IsraelRentals.PickYear.value,document.IsraelRentals.PickMonth.selectedIndex,document.IsraelRentals.PickDay.selectedIndex + 1);
			var dReturnDate = new Date(document.IsraelRentals.ReturnYear.value,document.IsraelRentals.ReturnMonth.selectedIndex,document.IsraelRentals.ReturnDay.selectedIndex + 1);			
			var gap = (dReturnDate - dPickDate)/86400000;
			//alert (dReturnDate);
							
			
                        if ((document.IsraelRentals.ReturnHour.selectedIndex - document.IsraelRentals.PickHour.selectedIndex > 1) || (document.IsraelRentals.ReturnHour.selectedIndex - document.IsraelRentals.PickHour.selectedIndex == 1 && document.IsraelRentals.ReturnMin.value - document.IsraelRentals.PickMin.value > -15)){
                            iHouresGap = 1;
                        }
                        
			if(gap + iHouresGap> 0)
			{
				//document.IsraelRentals.DayNum.value = gap+ iHouresGap;
				var daynum = gap + iHouresGap;
				daynum= String(daynum)
				//alert(xx);
				document.IsraelRentals.DayNum.value = IntNumber(daynum);//IntNumber(gap+ iHouresGap);
				//document.when_form.DayNum.value = IntNumber(xx);
				//alert("in alert");
			
			}
			else
			{
				document.IsraelRentals.DayNum.value = ""
				//alert("תאריך החזרה מוקדם מתאריך לקיחה")
			}
	}
	
	//set return date acording to days number
	function Set_ReturnDate()
	{       
                                
                if (document.IsraelRentals.DayNum.value == null || document.IsraelRentals.DayNum.value == "" || !isNum(document.IsraelRentals.DayNum.value)){
                    document.IsraelRentals.DayNum.value = "";
                    return;                    
                }

                var iHouresGap = 0;
                if ((document.IsraelRentals.ReturnHour.selectedIndex - document.IsraelRentals.PickHour.selectedIndex > 1) || (document.IsraelRentals.ReturnHour.selectedIndex - document.IsraelRentals.PickHour.selectedIndex == 1 && document.IsraelRentals.ReturnMin.value - document.IsraelRentals.PickMin.value > -15)){
                            iHouresGap = 1;
                }
                
                var iDaysToAdd = parseInt(document.IsraelRentals.DayNum.value) 
                var dPickDate = new Date(document.IsraelRentals.PickYear.value,document.IsraelRentals.PickMonth.selectedIndex,document.IsraelRentals.PickDay.selectedIndex + 1);
		var dReturnDate = new Date(dPickDate.getTime() + (iDaysToAdd-iHouresGap)*86400000);
		//alert(dReturnDate);
		
                document.IsraelRentals.ReturnDay.selectedIndex = dReturnDate.getDate() -1;
                document.IsraelRentals.ReturnMonth.selectedIndex = dReturnDate.getMonth();
                document.IsraelRentals.ReturnYear.value = dReturnDate.getFullYear();                                		
	}