#include <cstdio>
#include <cassert>
#include <cmath>
#include <cstring>

#include <algorithm>
#include <iostream>
#include <vector>
#include <map>
#include <set>
#include <functional>
#include <tuple>

#define _fetch(_1, _2, _3, _4, name, ...) name
#define rep2(i, n) rep3(i, 0, n)
#define rep3(i, a, b) rep4(i, a, b, 1)
#define rep4(i, a, b, c) for (int i = int(a); i < int(b); i += int(c))
#define rep(...) _fetch(__VA_ARGS__, rep4, rep3, rep2, _)(__VA_ARGS__)

using namespace std;

using i64 = long long;
using u8 = unsigned char;
using u32 = unsigned;
using u64 = unsigned long long;
using f80 = long double;

void solve() {
  static char S[1000010];
  static u64 rems[60000];
  const u64 mask = (u64(1) << 18) - 1;
  const u64 five18 = u64(1e18) >> 18;
  while (~scanf("%s", S)) {
    int len = strlen(S);
    int q = len / 18, r = len % 18;
    rep(i, q) {
      u64 n = 0;
      rep(j, 18) n = n * 10 + S[len - 18 + j] - '0';
      rems[i] = n; len -= 18;
    }
    if (r) {
      u64 n = 0;
      rep(j, r) n = n * 10 + S[len - r + j] - '0';
      rems[q++] = n; len -= r;
    }
    int ans = 0;
    while (q) {
      ans += __builtin_popcount(rems[0] & mask);
      rep(i, q) rems[i] = (rems[i] >> 18) + (rems[i + 1] & mask) * five18;
      if (rems[q - 1] == 0) --q;
    }
    printf("%d\n", ans);
  }
}

int main() {
  clock_t beg = clock();
  solve();
  clock_t end = clock();
  fprintf(stderr, "%.3f sec\n", double(end - beg) / CLOCKS_PER_SEC);
  return 0;
}