double dummy = 0.0;
    for (int i = 0; i < reps; i++) {
      dummy += algorithm.multipleQuantiles(ImmutableSet.of(90, 99), 100, dataset(i)).get(90);
    }
    return dummy;
  }

  @Benchmark
  double threePercentiles(int reps) {
    double dummy = 0.0;
    for (int i = 0; i < reps; i++) {
      dummy += algorithm.multipleQuantiles(ImmutableSet.of(90, 95, 99), 100, dataset(i)).get(90);
    }
    return dummy;
  }

    double singleQuantile(int index, int scale, double[] dataset) {
      Arrays.sort(dataset);
      return singleQuantileFromSorted(index, scale, dataset);
    }

    @Override
    Map<Integer, Double> multipleQuantiles(
        Collection<Integer> indexes, int scale, double[] dataset) {
      Arrays.sort(dataset);
      ImmutableMap.Builder<Integer, Double> builder = ImmutableMap.builder();
      for (int index : indexes) {