
import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int s = Integer.parseInt(scan.next());
        int w = Integer.parseInt(scan.next());
        scan.close();

        if (w >= s) {
            System.out.println("unsafe");
        } else {
            System.out.println("safe");
        }

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

    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int s = Integer.parseInt(scan.next());
        int w = Integer.parseInt(scan.next());
        scan.close();

        if (w >= s) {
            System.out.println("unsafe");
        } else {
            System.out.println("safe");
        }

    }
} Main public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int s = Integer.parseInt(scan.next());
        int w = Integer.parseInt(scan.next());
        scan.close();

        if (w >= s) {
            System.out.println("unsafe");
        } else {
            System.out.println("safe");
        }

    } main {
        Scanner scan = new Scanner(System.in);
        int s = Integer.parseInt(scan.next());
        int w = Integer.parseInt(scan.next());
        scan.close();

        if (w >= s) {
            System.out.println("unsafe");
        } else {
            System.out.println("safe");
        }

    } Scanner scan = new Scanner(System.in); scan new Scanner(System.in) int s = Integer.parseInt(scan.next()); s Integer.parseInt(scan.next()) Integer.parseInt Integer scan.next() scan.next scan int w = Integer.parseInt(scan.next()); w Integer.parseInt(scan.next()) Integer.parseInt Integer scan.next() scan.next scan scan.close() scan.close scan if (w >= s) {
            System.out.println("unsafe");
        } else {
            System.out.println("safe");
        } w >= s w s {
            System.out.println("unsafe");
        } System.out.println("unsafe") System.out.println System.out System System.out "unsafe" {
            System.out.println("safe");
        } System.out.println("safe") System.out.println System.out System System.out "safe" String[] args args public class Main {

    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int s = Integer.parseInt(scan.next());
        int w = Integer.parseInt(scan.next());
        scan.close();

        if (w >= s) {
            System.out.println("unsafe");
        } else {
            System.out.println("safe");
        }

    }
} public class Main {

    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int s = Integer.parseInt(scan.next());
        int w = Integer.parseInt(scan.next());
        scan.close();

        if (w >= s) {
            System.out.println("unsafe");
        } else {
            System.out.println("safe");
        }

    }
} Main

import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int s = Integer.parseInt(scan.next());
        int w = Integer.parseInt(scan.next());
        scan.close();

        if (w >= s) {
            System.out.println("unsafe");
        } else {
            System.out.println("safe");
        }

    }
}