private static long[] toArray(List<Long> input) {
    long[] result = new long[input.size()];
    for (int i = 0; i < result.length; i++) {
      result[i] = input.get(i);
    }
    return result;
  }
The percentile method returns the least value from the given list which has at least given percentile.
@param values The list of values to find the percentile from
@param percentile The percentile
@return The least value from the list with at least the given percentile
app/com/linkedin/drelephant/math/Statistics.java