def fast_int(st, tens=None):
  E = 16
  l = len(st)
  q, r = divmod(l, E)
  rs = []
  for i in range(q):
    rs.append(int(st[l-(i+1)*E:l-i*E]))
  if r:
    rs.append(int(st[:r]))
  ten = 10 ** (E // 2)
  while len(rs) > 1:
    ten *= ten
    nexts = []
    for i in range(len(rs) // 2): nexts += [rs[2 * i] + rs[2 * i + 1] * ten]
    if len(rs) & 1: nexts += [rs[-1]]
    rs = nexts
  return rs[0]

def solve():
  import sys
  for line in sys.stdin:
    print(bin(fast_int(line.rstrip())).count("1"))

solve()