import sys

def main(argv):

  #L = int(argv.pop())
  #tree = [int(s) for s in argv]
  n = int(argv[0])
  if n%2 == 0:
    print(n/2)
  else:
    print(int(n/2)+1)

if __name__ == '__main__':
    main(sys.argv[1:])
