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

int main(void){
    if(scanf("%19s",signal) !=1) return 0;
    if(strcmp(signal,"Red")== 0){
        printf("stop\n");
    }
    else if(strcmp(signal,"Yellow")== 0){
        printf("Ready\n");
        }
    else if(strcmp(signal,"Green")== 0){
        printf("Go\n");
    }
    else{
        printf("Invalid input\n");
    }
    return 0;
}