def may_mel2(p):
  bi = [0 for b in range(p)]
  bi.append(1)
  bi.reverse()
  for i in range(len(bi)):
    if bi[i] == 0:
      bi[i] = 1
      continue
    if bi[i] == 1:
      bi[i] = 0 
  print(bi.count(1))
may_mel2(int(input()))