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