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)

/**
 * Motto:   To Become Better Than Me
 * Author: cherry0697
 **/

 #include<bits/stdc++.h>
 using namespace std;

#define rep(i,n) for(i=0;i<n;i++)
#define repc(i,a,n) for(i=a;i<n;i++)
#define repa(i,a,n) for(i=a;i<=n;i++)
#define repb(i,a,n) for(i=a;i>=n;i--)
#define trav(a,x) for(auto a=x.begin();a!=x.end();a++)
#define all(x) x.begin(),x.end()
#define pb push_back
typedef long double ld;
typedef vector <long long int> vi;
typedef long long ll;

void solve()
{
  int s,w;
  cin>>s>>w;

  if(s>w) cout<<"safe"<<"\n";
  else cout<<"unsafe"<<"\n";
}

int main()
{
  ios_base::sync_with_stdio(0);
  cin.tie(0);

  int t;
  t=1;

  while(t--)
    solve();

return 0;
}