#include <iostream>
#include <string>
using namespace std;

int n;
string s;

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