#include <iostream>
#include <vector>
#include <string>
#include <cstring>
#include <math.h>
#include <cmath>
#include <limits.h>
#include <map>
#include <set>
#include <queue>
#include <algorithm>
#include <functional>
#include <stdio.h>
using namespace std;

long long MOD = 1000000007;

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