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: Wrong Answer)

#define _CRT_SECURE_NO_WARNINGS
#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
//#include <intrin.h>

#define fore(i,a,b) for(int i = a; i < (b); i++)
#define fr(i,a,b) for(int i = a - 1; i >= b; i--)
#define fast ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0)
#define N 300005
#define inf (ll)2e18
#define EPS 1e-12
#define MOD (ll)(1e9 + 7)
#define __builtin_popcount(x) __popcnt(x)

using namespace std;

typedef long long ll;

inline void solve()
{
	int s, w;
	cin >> s >> w;
	cout << (s > w) ? "safe" : "unsafe";
}

int main()
{
	fast;
#if defined(_DEBUG)
	freopen("input.txt", "r", stdin);
	freopen("output.txt", "w", stdout);
#endif
	int q = 1;
	//cin >> q;
	fore(t, 0, q)
	{
		solve();
		cout << '\n';
	}
}