import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int S = scanner.nextInt();
        int W = scanner.nextInt();

        System.out.println(W >= S ? "unsafe" : "safe");
    }
} import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int S = scanner.nextInt();
        int W = scanner.nextInt();

        System.out.println(W >= S ? "unsafe" : "safe");
    }
} Main public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int S = scanner.nextInt();
        int W = scanner.nextInt();

        System.out.println(W >= S ? "unsafe" : "safe");
    } main {
        Scanner scanner = new Scanner(System.in);
        int S = scanner.nextInt();
        int W = scanner.nextInt();

        System.out.println(W >= S ? "unsafe" : "safe");
    } Scanner scanner = new Scanner(System.in); scanner new Scanner(System.in) int S = scanner.nextInt(); S scanner.nextInt() scanner.nextInt scanner int W = scanner.nextInt(); W scanner.nextInt() scanner.nextInt scanner System.out.println(W >= S ? "unsafe" : "safe") System.out.println System.out System System.out W >= S ? "unsafe" : "safe" W >= S W S "unsafe" "safe" String[] args args public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int S = scanner.nextInt();
        int W = scanner.nextInt();

        System.out.println(W >= S ? "unsafe" : "safe");
    }
} public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int S = scanner.nextInt();
        int W = scanner.nextInt();

        System.out.println(W >= S ? "unsafe" : "safe");
    }
} Main
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int S = scanner.nextInt();
        int W = scanner.nextInt();

        System.out.println(W >= S ? "unsafe" : "safe");
    }
}