import java.util.Scanner;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner(System.in);

        int S = sc.nextInt();
        int W = sc.nextInt();
        String result = (W >= S) ? "unsafe" : "safe";

        System.out.println(result);
    }
} import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner(System.in);

        int S = sc.nextInt();
        int W = sc.nextInt();
        String result = (W >= S) ? "unsafe" : "safe";

        System.out.println(result);
    }
} Main public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner(System.in);

        int S = sc.nextInt();
        int W = sc.nextInt();
        String result = (W >= S) ? "unsafe" : "safe";

        System.out.println(result);
    } main {
        Scanner sc = new Scanner(System.in);

        int S = sc.nextInt();
        int W = sc.nextInt();
        String result = (W >= S) ? "unsafe" : "safe";

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

        int S = sc.nextInt();
        int W = sc.nextInt();
        String result = (W >= S) ? "unsafe" : "safe";

        System.out.println(result);
    }
} public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner(System.in);

        int S = sc.nextInt();
        int W = sc.nextInt();
        String result = (W >= S) ? "unsafe" : "safe";

        System.out.println(result);
    }
} Main
import java.util.Scanner;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner(System.in);

        int S = sc.nextInt();
        int W = sc.nextInt();
        String result = (W >= S) ? "unsafe" : "safe";

        System.out.println(result);
    }
}
