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(n/2+1)

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