#include <iostream>
#include <limits.h>
#include <string>

using namespace std;
int main(void){
    int n, ans = 0;
    string s;
    cin >> n;
    cin >> s;
    while (ans <= n) {
        if (s[ans] == 'x') {
            ans++;
            if (s[ans] == 'x') break;
            else ans++;
        }
        else ans++;
    }
    if (ans > n) ans = n;
    cout << ans << endl;
    return 0;
}
