function validateQunatity(form){
	var bookingQuantity = form.bookingQuantity.value;
	var quantity = form.quantity.value;
	var totalQuantity = form.totalQuantity.value;
	var availableQuantity = totalQuantity - bookingQuantity;
	if(quantity == '' || quantity <= 0){
		alert("Please provide the number of participant willing to join this sevayatra");
		form.quantity.focus();
		return false;
	}else{
		if(quantity > availableQuantity){
			alert("Number of participant entered is more than available number of participants. Only "+availableQuantity+" participant can book sevayatra");
			form.quantity.focus();
			return false;
		}else{
			return true; 
		}
	}
}