public boolean containsNumber(List<Integer> numbers, int comparisonNumber) {
  int low = 0;
  int high = numbers.size() - 1;
  while (low <= high) {
    int middle = low + (high - low) / 2;
    if (comparisonNumber < numbers.get(middle)) {
      high = middle - 1;
    } else if (comparisonNumber > numbers.get(middle)) {
      low = middle + 1;
    } else {
      return true;
    }
  }
  return false;
}