#include <bits/stdc++.h>
using namespace std;

int n;
string s;

int main() {
    cin >> n;
    cin >> s;
    for (int i = 0; i < n - 1; ++i) {
        if (s[i] == 'x' and s[i + 1] == 'x') {
            cout << i + 1 << endl;
            return 0;
        }
    }

    cout << n << endl;
    return 0;
}