/**
  * Changes the desired operationtype. ADDITION = 0; SUBTRACTION = 1; MULTIPLICATION = 2; DIVISION
  * = 3;
  *
  * @param operationType Integer; 0-3 for different operation types.
  */
 public void changeOperationType(int operationType) {
   student.setOperationType(operationType);
   this.questionsController =
       new QuestionsController(10, student.getDifficulty(), student.getOperationType());
 }
 /**
  * ADDITION = 0; SUBTRACTION = 1; MULTIPLICATION = 2; DIVISION = 3;
  *
  * @param playerName The students username
  * @param operationType Desired operation type; addition, substraction, multiplication, division.
  * @param difficulty Desired difficulty at game start. Will dynamically change to accomodate the
  *     students skill-level.
  */
 public GameController(String playerName, int operationType, int difficulty) {
   student = new Student(playerName);
   student.setOperationType(operationType);
   this.questionsController = new QuestionsController(10, difficulty, operationType);
   restoreGame();
 }