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

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