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

        int x = stdIn.nextInt();
        int y = stdIn.nextInt();
        if(x<=y){
            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) throws Exception {
       Scanner stdIn= new Scanner(System.in);

        int x = stdIn.nextInt();
        int y = stdIn.nextInt();
        if(x<=y){
            System.out.println("unsafe");
        }else{
            System.out.println("safe");
        }
    }
} Main public static void main(String[] args) throws Exception {
       Scanner stdIn= new Scanner(System.in);

        int x = stdIn.nextInt();
        int y = stdIn.nextInt();
        if(x<=y){
            System.out.println("unsafe");
        }else{
            System.out.println("safe");
        }
    } main {
       Scanner stdIn= new Scanner(System.in);

        int x = stdIn.nextInt();
        int y = stdIn.nextInt();
        if(x<=y){
            System.out.println("unsafe");
        }else{
            System.out.println("safe");
        }
    } Scanner stdIn= new Scanner(System.in); stdIn new Scanner(System.in) int x = stdIn.nextInt(); x stdIn.nextInt() stdIn.nextInt stdIn int y = stdIn.nextInt(); y stdIn.nextInt() stdIn.nextInt stdIn if(x<=y){
            System.out.println("unsafe");
        }else{
            System.out.println("safe");
        } x<=y x y {
            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) throws Exception {
       Scanner stdIn= new Scanner(System.in);

        int x = stdIn.nextInt();
        int y = stdIn.nextInt();
        if(x<=y){
            System.out.println("unsafe");
        }else{
            System.out.println("safe");
        }
    }
} public class Main {
    public static void main(String[] args) throws Exception {
       Scanner stdIn= new Scanner(System.in);

        int x = stdIn.nextInt();
        int y = stdIn.nextInt();
        if(x<=y){
            System.out.println("unsafe");
        }else{
            System.out.println("safe");
        }
    }
} Main
import java.util.Scanner;
public class Main {
    public static void main(String[] args) throws Exception {
       Scanner stdIn= new Scanner(System.in);

        int x = stdIn.nextInt();
        int y = stdIn.nextInt();
        if(x<=y){
            System.out.println("unsafe");
        }else{
            System.out.println("safe");
        }
    }
}
