https://www.pochta.ru/tracking?p_p_id=trackingPortlet_WAR_portalportlet&p_p_lifecycle=2&p_p_state=normal&p_p_mode=view&p_p_resource_id=tracking.get-by-barcodes&p_p_cacheability=cacheLevelPage&p_p_col_id=column-1&p_p_col_count=1

function recalculateprice()
{
    var main_price = 1505;
    var input_quantity = Number($('input[name="quantity"]').val());
    var special = 0;
    var tax = 0;
    discount_coefficient = 1;

    if (isNaN(input_quantity)) input_quantity = 0;

            main_price = process_discounts(main_price, input_quantity);
    tax = process_discounts(tax, input_quantity);
        

    var option_price = 0;

    
    $('input:checked,option:selected').each(function() {
        if ($(this).data('prefix') == '=') {
            option_price += Number($(this).data('price'));
            main_price = 0;
            special = 0;
        }
    });

    $('input:checked,option:selected').each(function() {
        if ($(this).data('prefix') == '+') {
            option_price += Number($(this).data('price'));
        }
        if ($(this).data('prefix') == '-') {
            option_price -= Number($(this).data('price'));
        }
        if ($(this).data('prefix') == 'u') {
            pcnt = 1.0 + (Number($(this).data('price')) / 100.0);
            option_price *= pcnt;
            main_price *= pcnt;
            special *= pcnt;
        }
        if ($(this).data('prefix') == 'd') {
            pcnt = 1.0 - (Number($(this).data('price')) / 100.0);
            option_price *= pcnt;
            main_price *= pcnt;
            special *= pcnt;
        }
        if ($(this).data('prefix') == '*') {
            option_price *= Number($(this).data('price'));
            main_price *= Number($(this).data('price'));
            special *= Number($(this).data('price'));
        }
        if ($(this).data('prefix') == '/') {
            option_price /= Number($(this).data('price'));
            main_price /= Number($(this).data('price'));
            special /= Number($(this).data('price'));
        }
    });

    special += option_price;
    main_price += option_price;

            tax = main_price;
    
    // Process TAX.
    main_price = calculate_tax(main_price);
    special = calculate_tax(special);

        if (input_quantity > 0) {
        main_price *= input_quantity;
        special *= input_quantity;
        tax *= input_quantity;
    }
    
    // Display Main Price
    animateMainPrice(main_price);

  }