#include <bits/stdc++.h>   using namespace std;   int main() {     int n, SF, FS;     SF = FS = 0;     string flights;     cin >> n >> flights;     for (int i = 0; i < flights.size() - 1; i++) {       if (flights[i] ==  S  && flights[i + 1] ==  F ) {         SF++;       } else if (flights[i] ==  F  && flights[i + 1] ==  S ) {         FS++;       }     }     if (SF > FS) {       cout <<  YES ;     } else {       cout <<  NO ;     }     return 0;   }   