#include <stdio.h>
#define rep(i,n) for(int i=0; i<(n); i++)

#define READ_A_CHAR getchar_unlocked


const char Colors[] = "ROYGCBV";
const char* Colors2[] = {"Red\n","Orange\n","Yellow\n","Green\n","Cyan\n","Blue\n","Violet\n"};
int getColorIdx(char c){ rep(t,7) if(Colors[t]==c) return t; }

int main(){
  int N=0;
  char c;
  while((c=READ_A_CHAR())!='\n') N=N*10+(c-'0');
  int C[7]={};
  rep(i,N-1){
    ++C[getColorIdx(READ_A_CHAR())];
    while(READ_A_CHAR()!=' ');
  }
  ++C[getColorIdx(READ_A_CHAR())];
  while(READ_A_CHAR()!='\n');
  rep(i,N-2){
    --C[getColorIdx(READ_A_CHAR())];
    while(READ_A_CHAR()!=' ');
  }
  --C[getColorIdx(READ_A_CHAR())];
  rep(t,7) if(C[t]) printf(Colors2[t]);
  return 0;
}