#include<bits/stdc++.h>
#define r(i,n) for(int i=0;i<n;i++)
using namespace std;
int n;
string s;
int main(){
	cin>>n>>s;
	r(i,n-1){
		if(s[i]=='x'&&s[i+1]=='x'){
			cout<<i+1<<endl;
			exit(0);
		}
	}
	cout<<n<<endl;
}