#include <stdio.h>
#include <stdio.h>
int main() {
    char s[20];
    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;
}