#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <utility>
#include <iomanip>
using namespace std;

int main(void) {
	int red = 0;
	string str;
	for (int i = 0; i < 3; i++) {
		cin >> str;
		if (str == "RED")	red++;
	}
	if (red > 1)	cout << "RED" << endl;
	else			cout << "BLUE" << endl;
	return 0;
}