#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <queue>
#include <cmath>
#include <climits>
#include <iomanip>
#include <set>
#include <map>
using namespace std;
typedef long long ll;
int main(){
    string a,b,c;
    cin >> a >> b >> c;
    ll sum = 0;
    if(a == "RED")sum++;
    if(b == "RED")sum++;
    if(c == "RED")sum++;
    if(sum >= 2)cout << "RED" << endl;
    else cout << "BLUE" << endl;
}