import java.util.Scanner;

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

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