At the end of the big preferential mall, discount scheme as follows, please enter the original shopping amount, after calculate the discount price and output,
When shopping amount less than or equal to 500 yuan, not discount;
When shopping amount between 500 yuan to 1000 yuan (contain 1000 yuan), 8 discount;
When shopping amount between 1000 yuan to 2000 yuan (contain 2000 yuan), 7.5 discount.
When shopping amount is more than 2000 yuan, 2000 yuan of the following section 7.5 fold, 2000 yuan of above part 6 fold,