public class Program {
public static void Main() {
string line;
while ((line = System.Console.ReadLine()) != null) {
string[] nums = line.Split(" ");
int x = int.Parse(nums[0]);
int y = int.Parse(nums[1]);
int z = int.Parse(nums[2]);
//任意两边之和大于第三边则能构成三角形
if (x + y > z && x + z > y && y + z > x) {
//等边三角形
if (x == y && x == z)
System.Console.WriteLine("Equilateral triangle!");
//等腰三角形
else if (x == y || x == z || y == z)
System.Console.WriteLine("Isosceles triangle!");
else
System.Console.WriteLine("Ordinary triangle!");
} else
System.Console.WriteLine("Not a triangle!");
}
}
}