#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <string>
#include <sstream>
#include <complex>
#include <algorithm>
#include <functional>
#include <vector>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <cmath>
#include <cassert>
#include <fstream>
#define REP(i,n) for(i=0;i<n;i++)
#define FOR(a,b) for(:a<b;a++)
#define SSTR( x ) static_cast< std::ostringstream & >( \
        ( std::ostringstream() << std::dec << x ) ).str()
using namespace std;
typedef long long unsigned int llu;
typedef long long ll;

int main (){
  int T;
  while(cin >> T){
    int a,i;
    bool isCorrect = true;
    a = 0;
    REP(i,T){
      int na;
      cin >> na;
      if(abs(a-na) != 1){
	isCorrect = false;
      }
      a = na;
    }
    
    if(isCorrect){
      cout << "T" << endl;
    }else{
      cout << "F" << endl;
    }
  }
  return 0;
}