#include<stdio.h>
#include<string.h>
int main()
{
    char signal[10];
    scanf("%s",signal);
    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;
}