TileGame free response answer

The TileGame problem from the 2009 AP Computer Science Exam is typical of free response problems that test Lists. The problem requires you to manipulate a List and the objects inside.

Review the TileGame free response problem with AP CS Tutor Brandon Horn.

TileGame Part (a): getIndexForFit

  private int getIndexForFit(NumberTile tile)
  {
    if (board.size() == 0 || tile.getRight() == board.get(0).getLeft())
      return 0;

    if (tile.getLeft() == board.get(board.size() - 1).getRight())
      return board.size();

    for(int i = 1; i < board.size(); i++)
      if(board.get(i - 1).getRight() == tile.getLeft() &&
           board.get(i).getLeft() == tile.getRight())
        return i;

    return -1;
  }

TileGame Part (b): insertTile

  public boolean insertTile(NumberTile tile)
  {
    for (int i = 1; i <= 4; i++)
    {
      int index = getIndexForFit(tile);
      if (index != -1)
      {
        board.add(index, tile);
        return true;
      }
      tile.rotate();
    }

    return false;
  }