#include <bits/stdc++.h>

using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> pairInt;
#define FOR(i, n) for (int i = 0; i < int(n); i++)
#define FOR1(i, m, n) for (int i = int(m); i < int(n); i++)
#define MAX(a, b) ((a) >= (b) ? (a) : (b))
#define MIN(a, b) ((a) <= (b) ? (a) : (b))

int main(int argc, char *argv[])
{
  int N;

  scanf("%d", &N);

  bool flag = false;
  int i = 0;
  while (i < N) {
    char c;
    scanf(" %c", &c);
    if (flag == true && c == 'x') {
      break;
    } else if (flag == false && c == 'x') {
      flag = true;
    } else {
      flag = false;
    }
    i++;
  }

  printf("%d\n", i);
  
  return 0;
}