#include <stdio.h>
int main()
{
    char traffic light signal;
    scanf("%c",&traffic light signal);
    if(s[0] == ''&'& s[1] == 'e' && s[2] == 'd' && s[3] == '\0')
    {
        printf("stop");
    }
    else if(s[0]='Y' && s[1] == 'e' && s[2] =='1' && s[3] =='1' && s[4] =='o' && s[5] =' 'w' && s[6] ='\0')
    {
        printf("Ready");
    }
    else if(s[0]=='G' && s[1] == 'r' && s[2] =='e' && s[3] == 'e' && s[4] =='n' && s[5] == '\0')
    {
    printf("Go");
    }
    else
    {
        printf("Invalid input");
    }