#include<stdio.h>
#include<string.h>
int main()
{
    char s[20];
    scanf("%d",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("Invaild input");
    }
    return 0;
}