#include<bits/stdc++.h>
using namespace std;

int main(){
    int a,b,c;
   cin >> a >> b >> c ;
   if(a+b<c||a+c<b||b+c<a){cout << "Not a triangle" << endl;}
  else if(a==b&&b==c){cout << "Equilateral" << endl;}
   else if(a==b&&b!=c||a==c&&a!=b||b==c&&b!=a){cout << "Isosceles" << endl;}
   else if(a!=b&&b!=c){cout << "Isosceles" << endl;}
}