Let's imagine that we have a fruit store. Every day in the store there are a number of activities, information about which is recorded in a file during the day. The current input file is sent to the program in CSV format (it is recommended to use standard libraries for parsing).

Your tasks are:

• read data from csv file
• process these data
• generate a report based on processed data
• write report to new csv file

There are four activities at the store:

    b - balance, the remnants of fruits at the beginning of the working day
    s - supply, means you are receiving new fruits from suppliers
    p - purchase, means someone has bought some fruit
    r - return, means someone who have bought the fruits now returns them back

Let's check in details all types of activities:

1. Balance. Fruit balance at the beginning of the work shift. The following line in the file will look like:

      b,banana,100  
   

   The line above means there are 100 bananas at the beginning of the work shift.

2. Supply. You are accepting new fruits from suppliers. The following line in the file will look like:

      s,banana,100     
   

   The line above means you receive 100 bananas.

3. Purchase. Buyers can visit your shop and buy some fruits. In this case you will have the following line in the file:

      p,banana,13  
   

   The line above means someone has bought 13 bananas.

4. Return. Buyers can return you some fruits. In this case you will have the following line in the file:

      r,banana,10   
   

   The line above means someone has returned you 10 bananas.

    type,fruit,quantity
    b,banana,20
    b,apple,100
    s,banana,100
    p,banana,13
    r,apple,10 
    p,apple,20 
    p,banana,5 
    s,banana,50

We are expecting to see how many fruits are available today after the work shift in your Fruit store.

    fruit,quantity
    banana,152
    apple,90

The line above means you have 152 bananas, and 90 apples in your Fruit store after the work shift.

Hint: Think about creating some FruitTransaction model to store info from file line for more convenient data processing (this is only a recommendation, you can use other classes / approaches to solve this task at your discretion):

public class FruitTransaction {
  private Operation operation;
  private String fruit;
  private int quantity;

  // getters, setters, ...
  
  public enum Operation {
    BALANCE("b"),
    SUPPLY("s"),
    PURCHASE("p"),
    RETURN("r");

    private String operation;

    Operation(String operation) {
      this.operation = operation;
    }

    public String getOperation() {
      return operation;
    }
  }
}