import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.StringTokenizer;

public class Main
{
	public static void main(String[] Arguments) throws IOException 
	{
		BufferedReader BR = new BufferedReader(new InputStreamReader(System.in)); StringTokenizer ST = new StringTokenizer(BR.readLine());
		int S = Integer.parseInt(ST.nextToken()), W = Integer.parseInt(ST.nextToken());
		System.out.println((W >= S) ? "unsafe" : "safe");
	}
} import java.io.BufferedReader; BufferedReader java.io import java.io.IOException; IOException java.io import java.io.InputStreamReader; InputStreamReader java.io import java.util.StringTokenizer; StringTokenizer java.util public class Main
{
	public static void main(String[] Arguments) throws IOException 
	{
		BufferedReader BR = new BufferedReader(new InputStreamReader(System.in)); StringTokenizer ST = new StringTokenizer(BR.readLine());
		int S = Integer.parseInt(ST.nextToken()), W = Integer.parseInt(ST.nextToken());
		System.out.println((W >= S) ? "unsafe" : "safe");
	}
} Main public static void main(String[] Arguments) throws IOException 
	{
		BufferedReader BR = new BufferedReader(new InputStreamReader(System.in)); StringTokenizer ST = new StringTokenizer(BR.readLine());
		int S = Integer.parseInt(ST.nextToken()), W = Integer.parseInt(ST.nextToken());
		System.out.println((W >= S) ? "unsafe" : "safe");
	} main {
		BufferedReader BR = new BufferedReader(new InputStreamReader(System.in)); StringTokenizer ST = new StringTokenizer(BR.readLine());
		int S = Integer.parseInt(ST.nextToken()), W = Integer.parseInt(ST.nextToken());
		System.out.println((W >= S) ? "unsafe" : "safe");
	} BufferedReader BR = new BufferedReader(new InputStreamReader(System.in)); BR new BufferedReader(new InputStreamReader(System.in)) StringTokenizer ST = new StringTokenizer(BR.readLine()); ST new StringTokenizer(BR.readLine()) int S = Integer.parseInt(ST.nextToken()) S Integer.parseInt(ST.nextToken()) Integer.parseInt Integer ST.nextToken() ST.nextToken ST W = Integer.parseInt(ST.nextToken()); W Integer.parseInt(ST.nextToken()) Integer.parseInt Integer ST.nextToken() ST.nextToken ST 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[] Arguments Arguments public class Main
{
	public static void main(String[] Arguments) throws IOException 
	{
		BufferedReader BR = new BufferedReader(new InputStreamReader(System.in)); StringTokenizer ST = new StringTokenizer(BR.readLine());
		int S = Integer.parseInt(ST.nextToken()), W = Integer.parseInt(ST.nextToken());
		System.out.println((W >= S) ? "unsafe" : "safe");
	}
} public class Main
{
	public static void main(String[] Arguments) throws IOException 
	{
		BufferedReader BR = new BufferedReader(new InputStreamReader(System.in)); StringTokenizer ST = new StringTokenizer(BR.readLine());
		int S = Integer.parseInt(ST.nextToken()), W = Integer.parseInt(ST.nextToken());
		System.out.println((W >= S) ? "unsafe" : "safe");
	}
} Main
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.StringTokenizer;

public class Main
{
	public static void main(String[] Arguments) throws IOException 
	{
		BufferedReader BR = new BufferedReader(new InputStreamReader(System.in)); StringTokenizer ST = new StringTokenizer(BR.readLine());
		int S = Integer.parseInt(ST.nextToken()), W = Integer.parseInt(ST.nextToken());
		System.out.println((W >= S) ? "unsafe" : "safe");
	}
}
