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 C++ (GCC 9.2.1) (judge verdict: Accepted)

#include <bits/stdc++.h>
using namespace std;
 
#define ll long long
#define fi first
#define se second
#define rep(i, n) for (int i = 0; i < (int)(n); ++i)
#define rep1(i, n) for (int i = 1; i <= (int)(n); ++i)
#define rep11(i, n) for (int i = 1; i < (int)(n); ++i)
#define rep0(i, n) for (int i = 1; i <= (int)(n); ++i)
#define repo(i, o, n) for (int i = o; i < (int)(n); ++i)
#define repm(i, n) for (int i = (int)(n)-1; i >= 0; --i)
#define all(v) (v).begin(), (v).end()
#define rall(v) (v).rbegin(), (v).rend()
#define pb(n) push_back(n)
#define mp make_pair
#define MOD 1002000007
#define INF LO

int main(){
    int s,w;
    cin>>s>>w;
    if(s<=w){
        cout<<"unsafe"<<endl;
    }
    else{
        cout<<"safe"<<endl;
    }
    

}