import java.util.*;

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

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