#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
#define pb push_back
#define mp make_pair
#define rep(i,n) for(int i=0;i<(n);++i)

int main(){
	cin.tie(0);
	ios::sync_with_stdio(false);
	int n;cin >> n;
	vector<int> a(n);
	rep(i,n) cin >> a.at(i);
	if(abs(a.at(0))!=1) cout << 'F' << endl;
	else{
		rep(i,n-1){
			if(abs(a.at(i+1)-a.at(i))!=1){
				cout << 'F' << endl;
				return 0;
			}
		}
		cout << 'T' << endl;
	}
}