How to calculate substitution

I created a class student, with 2 results for their exams. The first is Terminal marks and second is Exam marks. I created a method called average.

Here is the code for this method:

Code:

---

/ **
      * Calculates average of a list of integers
      * /
    public double average (List <integer> list)
    {
        double sum = 0.0;
        for (int i = 0; i <list.size () i = i +1)
        {
        sum = sum + list.get (i);
        }
        return sum/4;
    }

---

This method works great, when I type in display pane:

Integer[] numberArray = {75, 59, 0, 70};
Student.average (Arrays.asList (numberArray));

51 is the result which is correct.

My problem is to create the following method. I have to calculate the average of Terminal over Exam marks divided by 2. For example 51 + 64 / 2, which gives me the result of substitution of 57%. Here is my code:

Code:

---

/ **
      * Calculates and sets the substitutionScore of the receiver
      * /
    public void calcSubstitutionScore ()   
    {
        for (int aScore:scores)
        {
          this. results. put (aScore, new HashSet<String> ( ) ) ;
        }
          for (String average: students. keySet ())
          {
          for (String graded: this. results. get (average))
          {
          this. results. get (graded). add (average) / 2;
          }
          }
    }

---

Why does not it function? What is the error message?

It gives me a lot of syntax errors. For example for the line:

this.results.get (graded). add (average)/2;

It makes me: not a statement.

For the line:

for (int aScore : scores)

It makes me: cannot find symbol - variable score

I have in a class called Student: private int substitutionScore; Having 2 methods:

Code:

---

/ **
      * Sets the substitutionScore of the receiver to aScore
      * /
    private void setSubstitutionScore (int aScore)
    {
        this. substitutionScore = aScore;
    }

  / **
      * Returns the substitutionScore of the receiver
      * /
    public int getSubstitutionScore ()
    {
        return this. substitutionScore;
    }

---

In Java the use of the terms subject to different rules of visibility. It is not enough that you sent in your head, and so the Java will work.

As a very simple example:

Code:

---

{// Block
  {// Another block
    int quantity; // I declare my variable here
 
    quantity = 45 // good: the variable quantity is declared in the same block
    Quantity = 45 // syntax error here: quantity is not EQUAL to Quantity in Java
  }
  quantity = 45 // syntax error here: quantity is not declared in this block.
  }

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