#include <bits/stdc++.h>
using namespace std;

int command(char c){
	cout << c << endl;
	string s;cin >> s;
	if( s == "Merry" ){
		cin >> s;
		exit(0);
	}
	
	int n = stoi(s);
	return n;
}

int m[100][100];
void dfs(int x,int y,int dir){
	if( m[x][y] == 1 )return;
	m[x][y] = 1;
	//cerr << x << " " << y << " " << dir << endl;
	
	for(int i=0;i<4;i++){
		int n = command('L');
		if( n == 0 )continue;
		int ndir = dir+i+1;
		if( ndir%4 == 0 ){
			command('F');
			dfs( x+1, y, ndir);
			command('B');
		}else if( ndir%4 == 1 ){
			command('F');
			dfs( x, y+1, ndir);
			command('B');
		}else if( ndir%4 == 2 ){
			command('F');
			dfs( x-1, y, ndir);
			command('B');
		}else if( ndir%4 == 3 ){
			command('F');
			dfs( x, y-1, ndir);
			command('B');
		}
	}
}

int main(void){
	memset(m,-1,sizeof(m));
	string s;
	cin >> s;
	int sx = 50, sy = 50;
	dfs( sx, sy, 0);
	return 0;
}