#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <map>
#include <set>
#include <stdio.h>
#include <cstring>
#include <queue>
#include <stack>
#include <functional>
using namespace std;
#define Would
#define you

int b, r;
int main() {
	string h;
	for (int i = 0; i < 3; ++i) {
		cin >> h;
		if (h == "BLUE") { ++b; }
		else { ++r; }
	}
	string ans;
	if (r == 2) { ans = "RED"; }
	else { ans = "BLUE"; }
	cout << ans << endl;
}