Python implementation:

  def streaming_algorithm(A, epsilon, delta):
      # Initialize parameters
      p = 1
      X = set()
      thresh = math.ceil((12 / epsilon ** 2) * math.log(8 * len(A) / delta))

      # Process the stream
      for ai in A:
          if ai in X:
              X.remove(ai)
          if random.random() < p:
              X.add(ai)
          if len(X) == thresh:
              X = {x for x in X if random.random() >= 0.5}
              p /= 2
              if len(X) == thresh:
                  return '⊥'

      return len(X) / p


  # Example usage
  A = [1, 2, 3, 1, 2, 3]
  epsilon = 0.1
  delta = 0.01

  output = streaming_algorithm(A, epsilon, delta)
  print(output)