text: 
  a, b = 0, 1
  while b < 10:
      print(b)
      a, b = b, a + b
  
  # 1
  # 1
  # 2
  # 3
  # 5
  # 8
  a, b = 0, 1
  while b < 1000:
      print(b, end='->')
      a, b = b, a + b
  
  # 1->1->2->3->5->8->13->21->34->55->89->144->233->377->610->987->%
  