anchor.diff:      // swap two numbers in total
       for(int i = 0; i < 20; i++)
         swap2Numbers(tempSudoku);
  -
  -    print("Sudoku valid?: " + isValid(tempSudoku).toString());
   
       return tempSudoku;
     }
  
positive.code:     _sudoku.setGameField(_gameField);
      _sudoku.setUserInput(_userInput);
  
      return _sudoku;
    }
  
    void printSudoku(List<List<int>> sudoku) {
  
negative.code:     return transposedMatrix;
    }
  
  
    // TODO implementation
    // returns amount of possible solutions for given sudoku
  