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

int main(void){
	int n;
	string s;
	cin >> n >> s;

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

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