import java.util.*;


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


public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int hituji = sc.nextInt();
        int okami = sc.nextInt();
        if (hituji > okami) {
            System.out.println("safe");
        } else {
            System.out.println("unsafe");
        }
    }
}