
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
while (sc.hasNext()) {
int a = sc.nextInt();
int b = sc.nextInt();
int c = sc.nextInt();
int max = 0;
max = Math.max(a, b);
max = Math.max(max, c);
if (a == 0 && b == 0 && c == 0) {
break;
} else if (max * 2 >= a + b + c) {
System.out.println("Invalid");
} else if (a == b && b == c) {
System.out.println("Equilateral");
} else if (a == b || b == c || a == c) {
System.out.println("Isosceles");
} else if (a != b && b != c) {
System.out.println("Scalene");
}
}
}
}