#include <stdio.h>
#include <string.h>
int main() {
    char s[20];
    scanf("%s", s);
    if (strcump(s, "Red") == 0
    printf("stop");
    else if (strcump (s, "Yellow") == 0)
    printf("Ready");
    else if(strcmp(s, "Green") == 0)
    printf("Go");
    else
    printf("Invalid input");
    return 0;
}