#include <bits/stdc++.h>
using namespace std;
const int INF = 0x3f3f3f3f;
const double EPS = 1e-8;
const double PI = acos(-1);
template <class T>
bool chmax(T &a, const T &b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T>
bool chmin(T &a, const T &b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T>
ostream &operator<<(ostream &o, const vector<T> &t) {
  o << '[';
  for (__typeof((t).begin()) i = (t).begin(); i != (t).end(); ++i) {
    if (i != t.begin()) o << ',';
    o << *i;
  }
  return o << ']';
}
template <class S, class T>
ostream &operator<<(ostream &o, const pair<S, T> &t) {
  return o << '(' << t.first << ',' << t.second << ')';
}
template <int N, class Tp>
void out(ostream &, const Tp &) {}
template <int N, class Tp, class, class... Ts>
void out(ostream &o, const Tp &t) {
  if (N) o << ',';
  o << get<N>(t);
  out<N + 1, Tp, Ts...>(o, t);
}
template <class... Ts>
ostream &operator<<(ostream &o, const tuple<Ts...> &t) {
  o << '(';
  out<0, tuple<Ts...>, Ts...>(o, t);
  return o << ')';
}
template <class T>
void output(T *a, int n) {
  for (int i = 0; i < (int)(n); ++i) {
    if (i) cout << ',';
    cout << a[i];
  }
  cout << endl;
}
template <class T>
void output(T *a, int n, int m) {
  for (int i = 0; i < (int)(n); ++i) output(a[i], m);
}
template <class T>
void output(T t) {
  if (t < 0) t = -t, putchar(45);
  static int c[20];
  int k = 0;
  while (t) c[k++] = t % 10, t /= 10;
  for (k || (c[k++] = 0); k; putchar(c[--k] ^ 48))
    ;
}
template <class S, class... T>
void output(S a, T... t) {
  output(a);
  putchar(' ');
  output(t...);
}
template <class T>
bool input(T &t) {
  int n = 1, c;
  for (t = 0; !isdigit(c = getchar()) && ~c && c - 45;)
    ;
  if (!~c) return 0;
  for (c - 45 && (n = 0, t = c ^ 48); isdigit(c = getchar());
       t = 10 * t + c - 48)
    ;
  t = n ? -t : t;
  return 1;
}
template <class S, class... T>
bool input(S &a, T &...t) {
  input(a);
  return input(t...);
}
int main() {
  int n;
  while (cin >> n) {
    int t = 1;
    int ans = 0;
    for (int i = 0; i < (int)(n); ++i) {
      char c;
      cin >> c;
      if (c == '1' && t) {
        ans++;
      } else if (c == '0' && t) {
        ans++;
        t = 0;
      }
    }
    cout << ans << endl;
  }
}
