import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        if (sc.nextInt()>sc.nextInt())System.out.println("safe");
        else System.out.println("unsafe");
    }
} import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        if (sc.nextInt()>sc.nextInt())System.out.println("safe");
        else System.out.println("unsafe");
    }
} Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        if (sc.nextInt()>sc.nextInt())System.out.println("safe");
        else System.out.println("unsafe");
    } main {
        Scanner sc = new Scanner(System.in);
        if (sc.nextInt()>sc.nextInt())System.out.println("safe");
        else System.out.println("unsafe");
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) if (sc.nextInt()>sc.nextInt())System.out.println("safe");
        else System.out.println("unsafe"); sc.nextInt()>sc.nextInt() sc.nextInt() sc.nextInt sc sc.nextInt() sc.nextInt sc System.out.println("safe") System.out.println System.out System System.out "safe" System.out.println("unsafe") System.out.println System.out System System.out "unsafe" String[] args args public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        if (sc.nextInt()>sc.nextInt())System.out.println("safe");
        else System.out.println("unsafe");
    }
} public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        if (sc.nextInt()>sc.nextInt())System.out.println("safe");
        else System.out.println("unsafe");
    }
} Main
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        if (sc.nextInt()>sc.nextInt())System.out.println("safe");
        else System.out.println("unsafe");
    }
}
