@Override
		public void accept(final EvolutionResult<?, C> result) {
			if (_fitness.max() == null) {
				_fitness = MinMax.of(result.optimize().ascending());
			}

			super.accept(result);
		}
Return the minimal and maximal fitness.

@return minimal and maximal fitness
jenetics/src/main/java/io/jenetics/engine/EvolutionStatistics.java