#include<iostream>
using namespace std;

int main(){

  int n, i;
  string s;

  cin>>n;
  cin>>s;

  for(i=0;i<n;i++){
    if(s[i]=='x'&&s[i-1]=='x'){
      break;
    }
  }

  cout<<i<<endl;
  
  return 0;
}