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