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