import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class No00000516_Main {
	static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
	public static void main(String[] args) throws IOException {
		int r =0;
		for(int i = 0; i < 3; i++) {
			String c = br.readLine();
			if("RED".equals(c)) r++;
		}
		System.out.println(r > 1 ? "RED" : "BLUE");
	}
}