
import java.util.Scanner;

public class Main {

    /*
     * https://atcoder.jp/contests/abc164/tasks/abc164_a
     */

    public static void main(String[] args) {

        Scanner stdIn = new Scanner(System.in);
        String input = stdIn.nextLine();
        stdIn.close();

        String[] arguments = input.split(" ");
        int sheep = Integer.valueOf(arguments[0]);
        int wolf = Integer.valueOf(arguments[1]);

        if (sheep > wolf) {
            System.out.print("safe");
        } else {
            System.out.println("unsafe");
        }

    }
} import java.util.Scanner; Scanner java.util public class Main {

    /*
     * https://atcoder.jp/contests/abc164/tasks/abc164_a
     */

    public static void main(String[] args) {

        Scanner stdIn = new Scanner(System.in);
        String input = stdIn.nextLine();
        stdIn.close();

        String[] arguments = input.split(" ");
        int sheep = Integer.valueOf(arguments[0]);
        int wolf = Integer.valueOf(arguments[1]);

        if (sheep > wolf) {
            System.out.print("safe");
        } else {
            System.out.println("unsafe");
        }

    }
} Main public static void main(String[] args) {

        Scanner stdIn = new Scanner(System.in);
        String input = stdIn.nextLine();
        stdIn.close();

        String[] arguments = input.split(" ");
        int sheep = Integer.valueOf(arguments[0]);
        int wolf = Integer.valueOf(arguments[1]);

        if (sheep > wolf) {
            System.out.print("safe");
        } else {
            System.out.println("unsafe");
        }

    } main {

        Scanner stdIn = new Scanner(System.in);
        String input = stdIn.nextLine();
        stdIn.close();

        String[] arguments = input.split(" ");
        int sheep = Integer.valueOf(arguments[0]);
        int wolf = Integer.valueOf(arguments[1]);

        if (sheep > wolf) {
            System.out.print("safe");
        } else {
            System.out.println("unsafe");
        }

    } Scanner stdIn = new Scanner(System.in); stdIn new Scanner(System.in) String input = stdIn.nextLine(); input stdIn.nextLine() stdIn.nextLine stdIn stdIn.close() stdIn.close stdIn String[] arguments = input.split(" "); arguments input.split(" ") input.split input " " int sheep = Integer.valueOf(arguments[0]); sheep Integer.valueOf(arguments[0]) Integer.valueOf Integer arguments[0] arguments 0 int wolf = Integer.valueOf(arguments[1]); wolf Integer.valueOf(arguments[1]) Integer.valueOf Integer arguments[1] arguments 1 if (sheep > wolf) {
            System.out.print("safe");
        } else {
            System.out.println("unsafe");
        } sheep > wolf sheep wolf {
            System.out.print("safe");
        } System.out.print("safe") System.out.print System.out System System.out "safe" {
            System.out.println("unsafe");
        } System.out.println("unsafe") System.out.println System.out System System.out "unsafe" String[] args args public class Main {

    /*
     * https://atcoder.jp/contests/abc164/tasks/abc164_a
     */

    public static void main(String[] args) {

        Scanner stdIn = new Scanner(System.in);
        String input = stdIn.nextLine();
        stdIn.close();

        String[] arguments = input.split(" ");
        int sheep = Integer.valueOf(arguments[0]);
        int wolf = Integer.valueOf(arguments[1]);

        if (sheep > wolf) {
            System.out.print("safe");
        } else {
            System.out.println("unsafe");
        }

    }
} public class Main {

    /*
     * https://atcoder.jp/contests/abc164/tasks/abc164_a
     */

    public static void main(String[] args) {

        Scanner stdIn = new Scanner(System.in);
        String input = stdIn.nextLine();
        stdIn.close();

        String[] arguments = input.split(" ");
        int sheep = Integer.valueOf(arguments[0]);
        int wolf = Integer.valueOf(arguments[1]);

        if (sheep > wolf) {
            System.out.print("safe");
        } else {
            System.out.println("unsafe");
        }

    }
} Main

import java.util.Scanner;

public class Main {

    /*
     * https://atcoder.jp/contests/abc164/tasks/abc164_a
     */

    public static void main(String[] args) {

        Scanner stdIn = new Scanner(System.in);
        String input = stdIn.nextLine();
        stdIn.close();

        String[] arguments = input.split(" ");
        int sheep = Integer.valueOf(arguments[0]);
        int wolf = Integer.valueOf(arguments[1]);

        if (sheep > wolf) {
            System.out.print("safe");
        } else {
            System.out.println("unsafe");
        }

    }
}