#include <stdio.h>
int main()
{
    int age;
    
    scanf("%d", &age);
    
    if (age < 0) {
        printf("Invalid input\n");
    }
    else if (age < 18) {
        printf("Not eligible\n");
    }
    else {
        printf("Eligible\n");
        return 0;
    }
    }
        
    }
}