#include<stdio.h>
int main()
{
    scanf("%d", &score);
    if(score < 0)
    {
        printf("Invalid input\n");
    }
    else if(score > 75)
    {
        printf("Great job!\n");
    }
    else if (score >= 50 && score <= 75)
    {
        printf("Good effort!\n");
    }
    else
    {
        printf("Keep trying!\n");
    }
    return 0;
}