title: Add another element to an already filled index in arrayList
body: <p>I have a studentgradeprogram, I want to make it possible so that the user can set multiple grades for the students, but only the first input value is registered, i want all of them to be registered. And when I want to printout the studentgradelist, I want it to show all of the students with their all grades in one row.
  Like this: </p>
  
  <blockquote>
    <p>Hanna grade: 5, 6, 10, 4.<br>
    Emelie grade: 6, 7, 8, 3.</p>
  </blockquote>
  
  <p>Is it possible to create a gradelist for each instance of the class student?
  (Im using an arrayList)</p>
  
  <pre><code>public void register() {
  
      System.out.println("Studentname: ");
      String name = keyboard.nextLine();
  
      System.out.println("Grade: ");
      int grade = keyboard.nextInt();
  
  
      Student h1 = new Student(name, grade);
  
      gradeList.add(h1);
      System.out.println(name + " grade: " + grade);
  
      System.out.println("");
      keyboard.nextLine();
  }
  </code></pre>