def calculate_payment_amount(total_amount): if total_amount < 2000: return total_amount elif total_amount < 3000: return total_amount * 0.8 elif total_amount < 4000: return total_amount * 0.7 else: return total_amount * 0.6 # 测试 total_amount = int(input("请输入购买商品的总金额：")) actual_payment = calculate_payment_amount(total_amount) print("实际需要支付的金额为：{:.1f}".format(actual_payment))