private static <T extends Comparable<? super T>>
	int cmp(final T a, final T b) {
		if (a != null) {
			if (b != null) {
				return 2;
			} else {
				return 1;
			}
		} else {
			if (b != null) {
				return -1;
			} else {
				return 0;
			}
		}
	}
Return a {@code null}-friendly function which returns the worst element
of two values. E.g.

{@snippet lang="java":
assertNull(Optimize.MAXIMUM.<Integer>worst().apply(null, null));
assertEquals(Optimize.MAXIMUM.<Integer>worst().apply(null, 4), (Integer)4);
assertEquals(Optimize.MAXIMUM.<Integer>worst().apply(6, null), (Integer)6);
}

@see #worst(Comparable, Comparable)

@since 6.2

@param <C> the comparable argument type
@return a {@code null}-friendly method which returns the worst element of
	       two values
jenetics/src/main/java/io/jenetics/Optimize.java