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