#include <iostream>
#include <vector>
#include <string>
#include <array>
#include <map>
#include <cmath>
#include <cstdlib>

//using ll = long long;
using namespace std;

int main(){
  int n;
  cin>>n;
  string s;
  cin>>s;
  char c=s[0];
  for(int i=1;i<s.size();++i){
    if(c=='x' && s[i]=='x'){
      cout<<i<<endl;
      return 0;
    }
    c=s[i];
  }
  cout<<n<<endl;
  return 0;
}

