INT_BITS = 32

def getIndex(element):
  index = element / INT_BITS
  offset = element % INT_BITS
  bit = 1 << offset
  return (index, bit)

class Set:

  def __init__(self, capacity):
    self.capacity = capacity
    self.vector = range(1 + self.capacity / INT_BITS)
    for i in range(len(self.vector)):
      self.vector[i] = 0

  def add(self, element):
    (index, bit) = getIndex(element)
    self.vector[index] |= bit

  def delete(self, element):
    (index, bit) = getIndex(element)
    self.vector[index] &= ~bit

  def contains(self, element):
    (index, bit) = getIndex(element)
    return (self.vector[index] & bit) > 0