#include<iostream>
#include<string>
#include<string.h>
#include<algorithm>
#include<stdio.h>
#include<cmath>
#include<vector>
#include<utility>
#include<stack>
#include<queue>
#include<list>
#include<bitset>
#include<functional>

#define FOR(i, a, b) for(int i=(a);i<=(b);i++)
#define RFOR(i, a, b) for(int i=(a);i>=(b);i--)
#define MOD 1000000007
#define INF 1000000000

using namespace std;


int main(void) {
	int t;
	int x[101];
	bool flag = true;

	cin >> t;
	FOR(i, 1, t) {
		cin >> x[i];
	}
	x[0] = 0;

	FOR(i, 0, t-1) {
		if (abs(x[i] - x[i+1]) != 1) {
			flag = false;
			break;
		}
	}

	if (flag) {
		cout << "T" << endl;
	}
	else {
		cout << "F" << endl;
	}
	return 0;
}