import java.util.*;
public class Triangle
{
    public static void main(String[] args) 
    {
    Scanner sc=new Scanner(System.in);
    float l1=sc.nextFloat();
    float l2=sc.nextFloat();
    float l3=sc.nextFloat();
    if(l1<0||l2<0||l3<0)
    {
        System.out.println("Invalid input");
        return ;
    }
    if((l1+l2)>l3 ||())
    {
    if(l1==l2 && l2==l3)
    {
        System.out.println("equilateral");
    }
   else if(l1==l2 ||l2==l3 )
     {
      System.out.println("isosceles");
     } 
     else
     {
          System.out.println("scalene");
     }}
}}