import java.util.Scanner;

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

        int S = sc.nextInt();
        int W = sc.nextInt();

        System.out.println(solve(S, W));

        sc.close();
    }

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

        int S = sc.nextInt();
        int W = sc.nextInt();

        System.out.println(solve(S, W));

        sc.close();
    }

    static String solve(int S, int W) {
        return (S > W) ? "safe" : "unsafe";
    }
} Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        int S = sc.nextInt();
        int W = sc.nextInt();

        System.out.println(solve(S, W));

        sc.close();
    } main {
        Scanner sc = new Scanner(System.in);

        int S = sc.nextInt();
        int W = sc.nextInt();

        System.out.println(solve(S, W));

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

        int S = sc.nextInt();
        int W = sc.nextInt();

        System.out.println(solve(S, W));

        sc.close();
    }

    static String solve(int S, int W) {
        return (S > W) ? "safe" : "unsafe";
    }
} public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        int S = sc.nextInt();
        int W = sc.nextInt();

        System.out.println(solve(S, W));

        sc.close();
    }

    static String solve(int S, int W) {
        return (S > W) ? "safe" : "unsafe";
    }
} Main
import java.util.Scanner;

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

        int S = sc.nextInt();
        int W = sc.nextInt();

        System.out.println(solve(S, W));

        sc.close();
    }

    static String solve(int S, int W) {
        return (S > W) ? "safe" : "unsafe";
    }
}