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)

int main(void)
{
  int i, j, N;
  int x=0;
  scanf("%d", &N);
  
  char S[N][11];
  int y[N];
  
  for(i=0; i<N; i++)
    y[i]=0;
  
  for(i=0; i<N; i++)
    scanf("%s", S[i]);
  
  for(i=0; i<N-1; i++){
    for(j=i+1; j<N; j++){
      if(y[i]==0){
        if(S[i]==S[j]){
          x+=1;
          y[j]=1;
        }
      }
    }
  }
  printf("%d",N-x);
  return 0;
}