#include<stdio.h>
#include<string.h>
int main(){
    char signal[20];
    scanf("%s\n"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;
}