销售信息统计



沈阳的某家建材商店去年7月的销售业绩清单存储在文件file28,txt中，格式为：

售货员编号，售货员姓名，销售日期，销售额。写程序，对文件中的数据具有如下的统计分析功能：

①能够按照所制定的售货员的编号，或者姓名，统计出他在7月的销售总额。

②能够按照所制定的日期，统计出当日的销售总额。

-Sales Information Statistics Shenyang a home building materials store sales list last July results are stored in the file file28, txt, the format is: salesperson number, salesperson' s name, date of sale, sales. Written procedures for the data file has the following statistical analysis: ① formulated in accordance with the salesman' s number, or name, the statistics of his total sales in July. ② can be formulated in accordance with the date, the statistics of total sales for the day.