Problem:
Score : 100 points

Problem Statement

There are S sheep and W wolves.

If the number of wolves is greater than or equal to that of sheep, the wolves will attack the sheep.

If the wolves will attack the sheep, print unsafe; otherwise, print safe.

Constraints

1 \leq S \leq 100

1 \leq W \leq 100

Input

Input is given from Standard Input in the following format:

S W

Output

If the wolves will attack the sheep, print unsafe; otherwise, print safe.

Sample Input 1

4 5

Sample Output 1

unsafe

There are four sheep and five wolves. The number of wolves is not less than that of sheep, so they will attack them.

Sample Input 2

100 2

Sample Output 2

safe

Many a sheep drive away two wolves.

Sample Input 3

10 10

Sample Output 3

unsafe

Solution in Java (OpenJDK 11.0.6) (judge verdict: Runtime Error)

import java.util.Scanner;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.stream.Collectors;
public class Main {

	public static void main(String[] args) {
	int N;
 String st[];    
 Scanner sc = new Scanner(System.in);
    N = sc.nextInt();
    int i=0;
    ArrayList<String> strList = new ArrayList<String>();
    do {
    strList.add(sc.next());
    i++;
}while(i<N);
    System.out.println(strList.stream().collect(
            Collectors.groupingBy(x -> x, Collectors.counting())));
    
	}
	
	
	
	
	
	}