#include <bits/stdc++.h>
using namespace std;

//--------------------------------------------
#define FOR(i,a,b) for(int i=(a);i<(b);i++)
#define RFOR(i,a,b) for(int i=(b)-1;i>=(a);i--)
#define REP(i,n) FOR(i,0,n)
#define RREP(i,n) RFOR(i,0,n)
#define LL long long
#define INF INT_MAX/3

//--------------------------------------------
const double EPS = 1e-14;
const double PI  = acos(-1.0);

//--------------------------------------------

bool co(string s) {
  if (s == "RED") return 1;
  else return 0;
}

int main(){
  string a,b,c;
  cin >> a >> b >> c;
  int sum = co(a) + co(b) + co(c);
  if (sum >= 2) printf("RED\n");
  else printf("BLUE\n");
}