#include <iostream>
#include <string>

using namespace std;

int main()
{
	double speed;
	cin >> speed;

	if (speed <= 10) {
		cout << "slow" << endl;
	}
	else if (speed <= 50) {
		cout << "average" << endl;
	}
	else if (speed <= 150) {
		cout << "fast" << endl;
	}
	else if (speed <= 1500) {
		cout << "ultra fast" << endl;
	}
	else {
		cout << "extremely fast" << endl;
	}
    return 0;
}