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;


public class Main {
    
    public static void main(String[] args) {

        Scanner scanner = new Scanner(System.in);

        int times = scanner.nextInt();
        String[] prize = new String[times];

        int count = 0;
        boolean flg = true; //同じ要素がなかった場合にtrue

        for(int i = 0; i < times; i++) {
            
            prize[i] = scanner.next();

            for(int j = 0; j < i; j++) {
                if(prize[i].equals(prize[j])) {
                    flg = false;
                    break;
                } 
            }

            if(flg) {
                count++;
            }
            flg = true;
        }
    System.out.println(count);
    }
}