#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

#define RREP(i,s,e) for (i = s; i >= e; i--)
#define rrep(i,n) RREP(i,n,0)
#define REP(i,s,e) for (i = s; i < e; i++)
#define rep(i,n) REP(i,0,n)
#define INF 100000000

typedef long long ll;

int main() {
    int n;
    cin >> n;
    while (n != 20151224 && n > 0) {
        cout << "F" << endl;
        cin >> n;
    }
    if (n == 0) {
        cout << "L" << endl;
        cin >> n;
    }
    while (1) {
        if (n != 20151224) {
            cout << "R" << endl;
            cin >> n;
            while (n == 0) {
                cout << "L" << endl;
                cin >> n;
            }
        }
        cout << "F" << endl;
        cin.ignore();
        string s;
        getline(cin,s);
        if (s == "Merry Christmas!")
            break;
        n = stoi(s);
    }
    return 0;
}