import java.util.Scanner;
public class Main{
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
       
        int N = sc.nextInt();//羊
		int X = sc.nextInt();//  
           String x = (N>X) ?"safe":"unsafe";
           System.out.println(x);
     }
    } import java.util.Scanner; Scanner java.util public class Main{
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
       
        int N = sc.nextInt();//羊
		int X = sc.nextInt();//  
           String x = (N>X) ?"safe":"unsafe";
           System.out.println(x);
     }
    } Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
       
        int N = sc.nextInt();//羊
		int X = sc.nextInt();//  
           String x = (N>X) ?"safe":"unsafe";
           System.out.println(x);
     } main {
        Scanner sc = new Scanner(System.in);
       
        int N = sc.nextInt();//羊
		int X = sc.nextInt();//  
           String x = (N>X) ?"safe":"unsafe";
           System.out.println(x);
     } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int N = sc.nextInt(); N sc.nextInt() sc.nextInt sc int X = sc.nextInt(); X sc.nextInt() sc.nextInt sc String x = (N>X) ?"safe":"unsafe"; x (N>X) ?"safe":"unsafe" (N>X) N X "safe" "unsafe" System.out.println(x) System.out.println System.out System System.out x String[] args args public class Main{
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
       
        int N = sc.nextInt();//羊
		int X = sc.nextInt();//  
           String x = (N>X) ?"safe":"unsafe";
           System.out.println(x);
     }
    } public class Main{
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
       
        int N = sc.nextInt();//羊
		int X = sc.nextInt();//  
           String x = (N>X) ?"safe":"unsafe";
           System.out.println(x);
     }
    } Main
import java.util.Scanner;
public class Main{
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
       
        int N = sc.nextInt();//羊
		int X = sc.nextInt();//  
           String x = (N>X) ?"safe":"unsafe";
           System.out.println(x);
     }
    }
