include

using namespace std;

int main() {

int s;

cin >> s;
double b = s / 1.2;
double c = 1.0 * s / 3.0 + 50;
if (c > b);
cout << "bike";

{
	if  (b > c)
		cout << "wark";
}
if  (b == c)
	cout << "ok";

return 0;

}