Demand: The holiday conditions for each level of items within the monthly computing contract are as follows: 1. There are four levels of different levels in the contract, and the price is different; 2. Definition of the price of items at all levels is the price of monthly prices; 3. Every day The price is divided by the price of the items at all levels by 30; 4. Requires the price within the date segment of the input, (the deadline is greater than the start date, such as less than not to consider) 5. If the two days are less than a month, it is less than a month 15 days, the total price is calculated according to the number of days; it is greater than or equal to 15 days. 6. If the two-day difference is greater than one month, the total price is calculated on the month, and the total price is calculated on a monthly basis; 7. More than one month and non-all moon It is less than 15 days, the total price is calculated by the number of days; it is more than 15 days calculations.
Implementation: Evaluates the specified time period the total contract price: