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

int main( int argc, char *argv[] )
{
char S[ 4 ][ 10 ];
int iCnt;

	ios::sync_with_stdio( false );
	cin.tie( 0 );

	cin >> S[ 0 ];
	cin >> S[ 1 ];
	cin >> S[ 2 ];

	iCnt = 0;
	if( S[ 0 ][ 0 ] == 'B' ) iCnt++;
	if( S[ 1 ][ 0 ] == 'B' ) iCnt++;
	if( S[ 2 ][ 0 ] == 'B' ) iCnt++;

	if( iCnt >= 2 )
		cout << "BLUE" << endl;
	else
		cout << "RED" << endl;

	return 0;
}