Implement method getStatistic(String fromFileName, String toFileName)
which will return some data from market after working day.
This method has two parameters:
String fromFileName
- you should read data from this fileString toFileName
- you should write result to this file
Input file has .csv
format. CSV is a simple file format used to store tabular data.
This type of files is very popular to storing information. So we will start working with it.
CSV stands for "comma-separated values". Its data fields are most often separated, or delimited by a comma.
For example, let's say you had a spreadsheet containing the following data:
operation type | ammount |
---|---|
supply | 30 |
buy | 10 |
buy | 13 |
supply | 17 |
buy | 10 |
The above data could be represented in a CSV-formatted file as follows:
supply,30
buy,10
buy,13
supply,17
buy,10
Your task is to read all data from input csv file, create a report and write it to newFile (the name of this file is the second parameter in the method).
Example of the report:
supply,47
buy,33
result,14
Explanation:
supply = 30 + 17 = 47
buy = 10 + 13 + 10 = 33
result = supply - buy = 47 - 33 = 14