#include<stdio.h>
#include <iostream>
#include <cstring>
using namespace std;


int main(){
	

	char a1[10],a2[10],a3[10];
	cin>>a1>>a2>>a3;
	char *b;
	b="BLUE";
	int i=0;
	if(!strcmp(a1,b)) i++;
	if(!strcmp(a2,b)) i++;
	if(!strcmp(a3,b)) i++;
	if(i>1) printf("BLUE\n");
	else printf("RED\n");

	

	
	return 0;
}