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 JavaScript (Node.js 12.16.1) (judge verdict: Wrong Answer)

"use strict";
const main = arg => {
  const input = arg.trim().split('\n');
  const arr = input[0].split(" ").map(Number);
  
  let tLife = arr[0];
  const tPower = arr[1];
  let aLife = arr[2];
  const aPower = arr[3];
  
  let cnt = 0;
  
  while((tLife <= 0) || (aLife <= 0)){
        
        if((cnt % 2) === 0){
    		aLife -= tPower;
        }else{
          	tLife -= aPower;
        }
	cnt++;
  }
  
  if(tLife <= 0){
    console.log("No");
  }else{
    console.log("Yes");
  }
}
 
main(require("fs").readFileSync("/dev/stdin", "utf8"));