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: Accepted)

import java.util.Scanner;


public class Main {


//	final int MOD = 1000000007;


	public static void main(String[] args) {

		int ans = 0;
		Scanner sc = new Scanner(System.in);
		boolean f = false;

		int n = sc.nextInt();
		int k = sc.nextInt();


		//-------------------------------------------------------------------------------------

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

		//-------------------------------------------------------------------------------------

//		for(int i = 0; i < n; i++) {
//			System.out.println(ans[i]);
//		}

//		if(f) {
//			System.out.println("Yes");
//		} else {
//			System.out.println("No");
//		}

//		System.out.println(ans);

		sc.close();
	}
}