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