#include<bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int,int>;
#define rep(i,n) for(int i=0; i<n; i++)
#define UNIQUE(v) v.erase(unique(v.begin(), v.end()), v.end()) //sortしてから使う
#define INF 2147483647
#define LLINF 9223372036854775807LL

int main(){
  int red = 0;
  rep(i,3){
    string s; cin>>s;
    if (s=="RED") red++;
  }
  if (red>=2) cout << "RED" << endl;
  else cout << "BLUE" << endl;
}