#include<iostream>
#include<string>
#include<algorithm>
#include<cctype>
#include<set>
#include<bitset>
#include<math.h>
#include<map>
#include<queue>
#include<iomanip>
using namespace std;

int main(){
    int r = 0;
    string s;
    for (int i = 0; i < 3; i++){
        cin >> s;
        if (s == "RED") r += 1;
    }
    cout << ((r > 1) ? "RED" : "BLUE") << endl;
}