class PiePiece {
  public:
    PiePiece(int percent, Pattern* pattern);
    /*
     * Construct a piece of a PieChart (q.v.), of the given percentage of the
     * total pie and the given pattern.  The given percent should be between 1
     * and 100, inclusive.  If < 1, 1 will be used.  If > 100, 100 will be
     * used.
     */

    int GetSize();
    /*
     * Return the size of the piece, as a percentage between 1 and 100,
     * inclusive.
     */

  protected:
    int percent;	/* The percent of a whole pie. */
    Pattern* pattern;	/* The pattern to draw the piece in. */
};

class PieChart : Picture {
  public:
    PieChart(int n, int r, ...);
    /*
     * Consruct a pie chart of n pieces, radius length r.  The varargs that
     * follow must be n args of type PiePiece.  The numeric percentage of all n
     * pieces should total 100.  If the total is < 100, a white piece will be
     * added to fill the remainder.  If the total is > 100, only as many pieces
     * will be drawn as total < 100, and the last piece will be truncated in
     * size, if necessary, to fill the remainder, if any.
     */
};