#include <stdio.h>
#include <string.h>

int main()
{
    char s[10];
    scanf("%s", s);
    if (strcmp(s, "Red")==0){
        printf("Stop");
    }else if(strcmp(s, "Yellow")==){
        printf("Ready");
        } else if(strcmp(s,"Green")==0){
            printf("Go");
        }else{
            printf("Invalid input");
            
        }
        return 0:
        }