output_description: Print the answer.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      N
attempt: def s_in():
      return input()
  
  
  def n_in():
      return int(input())
  
  
  def l_in():
      return list(map(int, input().split()))
  
  
  class Interval:
      def __init__(self, li):
          self.li = li
          self.n = len(li)
          self.sum_li = [li[0]]
          for i in range(1, self.n):
              self.sum_li.append(self.sum_li[i - 1] + li[i])
  
      def sum(self, a, b=None):
          if b is None:
              return self.sum(0, a)
  
          res = self.sum_li[min(self.n - 1, b - 1)]
          if a > 0:
              res -= self.sum_li[a - 1]
          return res
  
  
  import math
  
  N = n_in()
  print(math.ceil(N / 2))
  
problem_description: Statement
  
  Takahashi wants to print a document with N pages double-sided, where two pages
  of data can be printed on one sheet of paper.
  
  At least how many sheets of paper does he need?
samples: [{"input": "5", "output": "3\n    \n\nBy printing the 1-st, 2-nd pages on the 1-st sheet, 3-rd and 4-th pages on the\n2-nd sheet, and 5-th page on the 3-rd sheet, we can print all the data on 3\nsheets of paper.\n\n* * *"}, {"input": "2", "output": "1\n    \n\n* * *"}, {"input": "100", "output": "50"}]