output_description: Print the number of the integers between a and b, inclusive, that are
  divisible by x.
  
  * * *
input_description: The input is given from Standard Input in the following format:
  
      
      
      a b x
attempt: from decimal import *
  
  # exp = Decimal(10**23)
  # rint((Decimal(11)*exp)/Decimal(10))
  
  ## coding: UTF-8
  s = input().split()
  t = [int(p) for p in s]
  # print(t)
  
  a = t[0]
  b = t[1]
  x = t[2]
  
  """
  start = a
  goal = b
  while True:
      if(start % x == 0):
          break
      else:
          start += 1
  #print(start)
  while True:
      if(goal % x == 0):
          break
      else:
          goal -= 1
  #start = Decimal(3)
  #goal = Decimal(999999999999999999)
  
  #print(Decimal(goal))
  print(Decimal(Decimal(Decimal(goal) - Decimal(start)) / Decimal(x)) + Decimal(1)  ) 
  #answer = ((goal - start) / x ) + 1
  #print('{}'.format(int(answer)))
  """
  
  
  def count_even(t, x):
      return int(Decimal(t) / Decimal(x))
  
  
  if a == 0:
      answer = count_even(b, x) + 1
  else:
      answer = count_even(b, x) - count_even(a - 1, x)
  print(answer)
  
problem_description: Statement
  
  You are given nonnegative integers a and b (a ≤ b), and a positive integer x.
  Among the integers between a and b, inclusive, how many are divisible by x?
samples: [{"input": "4 8 2", "output": "3\n    \n\nThere are three integers between 4 and 8, inclusive, that are divisible by 2:\n4, 6 and 8.\n\n* * *"}, {"input": "0 5 1", "output": "6\n    \n\nThere are six integers between 0 and 5, inclusive, that are divisible by 1: 0,\n1, 2, 3, 4 and 5.\n\n* * *"}, {"input": "9 9 2", "output": "0\n    \n\nThere are no integer between 9 and 9, inclusive, that is divisible by 2.\n\n* * *"}, {"input": "1 1000000000000000000 3", "output": "333333333333333333\n    \n\nWatch out for integer overflows."}]