import java.util.Scanner;
import java.util.Arrays;

public class Main{
public static void main(String[] args){
Scanner scan=new Scanner(System.in);
int n=scan.nextInt();
int m=scan.nextInt();

if(n<=m){
System.out.println("unsafe");
}else{
System.out.println("safe");
}

}
} import java.util.Scanner; Scanner java.util import java.util.Arrays; Arrays java.util public class Main{
public static void main(String[] args){
Scanner scan=new Scanner(System.in);
int n=scan.nextInt();
int m=scan.nextInt();

if(n<=m){
System.out.println("unsafe");
}else{
System.out.println("safe");
}

}
} Main public static void main(String[] args){
Scanner scan=new Scanner(System.in);
int n=scan.nextInt();
int m=scan.nextInt();

if(n<=m){
System.out.println("unsafe");
}else{
System.out.println("safe");
}

} main {
Scanner scan=new Scanner(System.in);
int n=scan.nextInt();
int m=scan.nextInt();

if(n<=m){
System.out.println("unsafe");
}else{
System.out.println("safe");
}

} Scanner scan=new Scanner(System.in); scan new Scanner(System.in) int n=scan.nextInt(); n scan.nextInt() scan.nextInt scan int m=scan.nextInt(); m scan.nextInt() scan.nextInt scan if(n<=m){
System.out.println("unsafe");
}else{
System.out.println("safe");
} n<=m n m {
System.out.println("unsafe");
} System.out.println("unsafe") System.out.println System.out System System.out "unsafe" {
System.out.println("safe");
} 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 scan=new Scanner(System.in);
int n=scan.nextInt();
int m=scan.nextInt();

if(n<=m){
System.out.println("unsafe");
}else{
System.out.println("safe");
}

}
} public class Main{
public static void main(String[] args){
Scanner scan=new Scanner(System.in);
int n=scan.nextInt();
int m=scan.nextInt();

if(n<=m){
System.out.println("unsafe");
}else{
System.out.println("safe");
}

}
} Main
import java.util.Scanner;
import java.util.Arrays;

public class Main{
public static void main(String[] args){
Scanner scan=new Scanner(System.in);
int n=scan.nextInt();
int m=scan.nextInt();

if(n<=m){
System.out.println("unsafe");
}else{
System.out.println("safe");
}

}
}