#include <iostream>
#include <algorithm>
#include <cmath>
#include <vector>
#include <complex>
#include <queue>
#include <deque>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <iomanip>
#include <assert.h>
#include <array>
#include <cstdio>
#include <cstring>
#include <random>
#include <functional>
#include <numeric>
#include <bitset>

using namespace std;

#define REP(i,a,b) for(int i=a;i<(int)b;i++)
#define rep(i,n) REP(i,0,n)
#define all(c) (c).begin(), (c).end()
#define zero(a) memset(a, 0, sizeof a)
#define minus(a) memset(a, -1, sizeof a)
#define minimize(a, x) a = std::min(a, x)
#define maximize(a, x) a = std::max(a, x)

typedef long long ll;
int const inf = 20151224;

int in;
void isover(string const& in_) {
  if(in_ == "Merry") {
//  if(in_ == "Merry Christmas!") {
    exit(0);
  }
  in = stoi(in_);
}

int main() {

  string in_;
  while(1) {
    cin >> in_; isover(in_);
    if(0 < in && in < inf) {
      cout << "F" << endl; cout << flush;
    }
    else if(in == 0) {
      cout << "L" << endl; cout << flush;
    }
    else {
      cout << "F" << endl; cout << flush;
    }
  }

  return 0;
}