#define _CRT_SECURE_NO_WARNINGS
#include
void main()
{
int N, i, r = 0, y = 0;
char a[15];
while (1)
{
scanf("%d", &N);
if (N == 0)
break;
for (i = 0; i < N; i++)
{
scanf("%c", &a[i]);
if (a[i] == 'R')
r++;
if (a[i] == 'Y')
y++;
}
if (r < 7 && a[N - 1] == 'B')
printf("Yellow\n");
if (y < 7 && a[N - 1] == 'L')
printf("Red\n");
if (r == 7 && a[N - 1] == 'B')
printf("Red\n");
if (y == 7 && a[N - 1] == 'L')
printf("Yellow\n");
}
}