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 Python (3.8.2) (judge verdict: Wrong Answer)

import sys
input = sys.stdin.readline
def print_ans(S, W):
    """Test Case
    >>> print_ans(4, 5)
    'unsafe'
    >>> print_ans(100, 2)
    'safe'
    >>> print_ans(10, 10)
    'unsafe'
    """
    if S > W :
         return 'safe'
    else:
        return 'unsafe'
if __name__ == '__main__':
    S, W = map(int, input().rstrip().split())
    print_ans(S, W)