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 <string>
#include <cmath>
#include <sstream>
#define FOR(i, a, b) for (int i = (a); i < (b); i++)
#define FORD(i, a, b) for(int i = (a-1); i >= (b); i--)
#define pb(a) push_back(a)
#define mp(a,b) make_pair(a,b)
typedef long long int ll;
using namespace std;
//ll mod=1000000007;
//ll mod=67280421310721;
ll mod=998244353;
ll INF=1e18;
ll po(ll a,ll b)
{
	ll re=1;
	while(b)
	{
		if(b%2==1)
		{
			re=(re*a);
			re%=mod;
		}
		a=(a*a);
		a%=mod;
		b>>=1;
	}
	return re;
}
int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);
	int test=1;
//	cin>>test;
	while(test--)
	{
		int s,w;
		cin>>s>>w;
		if(s>w)
		cout<<"safe";
		else
		cout<<"unsafe";
	}
	return 0;
}