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>
#include <boost/multiprecision/cpp_int.hpp>
#define rep(i,m,n) for(int i=m;i<n;i++)
#define co(n) cout<<n<<endl
#define all(n) (n).begin(),(n).end()
#define pb(n,m) n.push_back(m)
#define pi(n,m) n.insert(n.begin(),m);
#define ee(n) n.erase(n.end()-1)
#define eb(n) n.erase(n.begin())
#define check(n) reverse(all(n));rep(z,0,n.size())cout<<n[z];co("");reverse(all(n));
using namespace std;
namespace mp=boost::multiprecision;
typedef long long ll;
typedef unsigned long long ull;
using bint=mp::cpp_int;

int main(){
  int n,m;
  cin>>n>>m;
  if(n<=m) co("unsafe");
  else co("safe");
  return 0;
}