#import<stdio.h>
#define Z(S,N)puts(S),fflush(stdout),scanf("%d",&N);
N;main(x){for(gets(&N);;){
	for(x=99,Z("L",N)--x;){
		Z("R",N)
		for(;!N;)Z("L",N)
		if(N>50){for(x=50;--x;)puts("F");exit(0);}
		Z("F",N)
	}
	for(;N--;)Z("F",x)
}}