#include <iostream>
using namespace std;

int main() {
	int n,p = 0,x;
	cin >> n;
	for(int t = 0;t<n;t++){
		cin >> x;
		if(x == p||!(p-x==1||p-x==-1)){
		cout << "F";
		return 1;
		}
                p = x;
	}
	cout << "T";
	return 0;
}