code: public CompensatedSum add(CompensatedSum other) {
  		double correctedSum = other.value() + (delta + other.delta());
  		double updatedValue = value + correctedSum;
  		double updatedDelta = correctedSum - (updatedValue - value);
  		return new CompensatedSum(updatedValue, updatedDelta);
  	}
docs: Increments the Kahan sum by adding two sums, and updating the correction term for reducing numeric errors.