#include <iostream>

using namespace std;

int main() {
    int a, b, c;
    cin >> a;
    cin >> b;
    cin >> c;
    if (a+b+c > 180 || (a==0) || (b==0)|| (c==0)) {
        cout <<" Not a triangle";
    }
    else {
        if (a + b + c == 180) {
            if (a == b && b == c) {
                cout << "Equilateral triangle" << endl;
            }
            else {
                if ((a && b == 45) || (a && c == 45) || (b && c == 45)) {
                    cout << "Rectangular isosceles triangle" << endl;
                } else {
                    if ((a + b == 90) || (a + c == 90) || (b + c == 90) || (a == 90) || (b == 90) || (c == 90)) {
                        cout << "Rectangular triangle" << endl;
                    }
                else {
                    if ((a == b) || (a == c) || (b == c)) {
                        cout << "Isosceles triangle" << endl;
                    }
                        else{
                        cout << "common triangle";
                    }
                    }
                }
            }

        }
    }
}