#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  while (scanf("%d", &n) != EOF) {
    char s[105];
    scanf("%s", s);
    int l = strlen(s);
    int sum = 0;
    for (int i = 0; i < l; i++) {
      sum++;
      if (s[i] == '0') break;
    }
    printf("%d\n", sum);
  }
  return 0;
}
