#include <bits/stdc++.h>
using namespace std;
using LL = long long;
using PII = pair<int, int>;
int main() {
  int n;
  string s;
  cin >> n >> s;
  char l = 0;
  int ans = 0;
  for (char c : s) {
    if (l == 'x' && c == 'x') break;
    ans++;
    l = c;
  }
  cout << ans << endl;
  return 0;
}
