#include <iostream>
using namespace std;
int main() {
    int a, b, c;
    cin >> a >> b >> c;
    if(a + b > c && a + c > b && b + c > a){
        if(a == b && a == c && b == c){
            cout << "Equilateral triangle!";
        }
        else if(a == b || a == c || b == c){
            cout << "Isosceles triangle!";
        }
        else cout << "Ordinary triangle!";
    }
    else cout << "Not a triangle!";
}