#include<stdio.h>
#include <string.h>
int main(){
    char s[10];
    
    fgets(s,sizeof(s);
    
    if (strcmp(s, "Red"){
        printf("Stop");
    }else if(strcmp(s, "Yellow"){
        printf("Ready");
    }else if(strcmp(s, "Green"){
        printf("Go");
    }else{
        printf("Invalid input");
    }
    return 0;
}