import java.util.Arrays;
import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        while (sc.hasNextInt()) {
            int[] nums = new int[3];
            for (int i = 0; i < 3; i++) {
                nums[i] = sc.nextInt();
            }
            Arrays.sort(nums);
            int flag = nums[0] * nums[0] + nums[1] * nums[1] - nums[2] * nums[2];
            if (flag > 0) System.out.println("锐角三角形");
            else if (flag == 0) System.out.println("直角三角形");
            else System.out.println("钝角三角形");
        }
    }
}