// No.516 赤と青の風船
package main

import (
	"fmt"
	"strings"
)

func main() {
	var s1, s2, s3 string
	fmt.Scan(&s1, &s2, &s3)

	r := strings.Count(s1+s2+s3, "R")
	if r > 1 {
		fmt.Println("RED")
	} else {
		fmt.Println("BLUE")
	}
}