#include <bits/stdc++.h>
using namespace std;
int main() {
  string s;
  long long t, j = 0;
  cin >> t;
  cin >> s;
  for (long long i = 0; i < s.size(); i++) {
    if (s[i] == 'F')
      if (s[i + 1] == 'S') j--;
    if (s[i] == 'S')
      if (s[i + 1] == 'F') j++;
  }
  if (j <= 0)
    cout << "NO";
  else if (j > 0)
    cout << "YES";
  return 0;
}
