#include <iostream>
#include <list>
#include <vector>
#include <string>
#include <stdio.h>
#include <stdint.h>
#include <iomanip>
using namespace std;

using uint = unsigned int;
using ll = long long;

#define CIN( LL , A ) LL A; cin >> A 
#define GETLINE( A ) string A; getline( cin , A ) 
#define FOR_ITR( ARRAY , ITR , END ) for( auto ITR = ARRAY .begin() , END = ARRAY .end() ; ITR != END ; ITR ++ ) 

int main()
{

  string S;
  const string RED = "RED";
  ll num = 0;

  for( uint i = 0 ; i < 3 ; i++ ){

    cin >> S;
    
    if( S == RED ){

      num++;

    } else {

      num--;

    }

  }

  const string answer = num > 0 ? RED : "BLUE";
  cout << answer << endl;
  return 0;

}